Introducing fastlane precheck: Submit your app to the app store with confidence

By Joshua Liebowitz, Software Engineer

Introducing-fastlane-precheck

We’ve all been in this situation before: you work tirelessly to build a great app, you spend countless hours beta testing and fixing bugs, and you even put together a comprehensive marketing plan in time for your app’s launch. Months of anticipation finally culminate when you submit your app to the app store… but instead of celebrating the new release, you find out that your app didn’t meet the right criteria for listing so it got rejected 😱.

There’s nothing quite as deflating as tripping at the finish line.

App store guidelines can be complicated and hard to remember because they’re constantly changing, but developers still need to follow them in order to get their apps approved. Sometimes, these guidelines get overlooked or lost in the shuffle of all the other important pre-launch tasks. To help you avoid unnecessary delays and rejection, we’re excited to introduce fastlane precheck for iOS apps! You can count on us to remember the rules so you can submit your app with confidence.

Review your app in seconds to save days of delays

Often, apps get rejected from app stores because of simple, solvable issues with their metadata (such as title, description, changelog, keywords, etc.). Once rejected, you have to resubmit your app and it can take days before it’s reviewed again. This wastes time and can throw off your schedule.

Instead of risking rejection or painstakingly auditing your own metadata, you can now use fastlane precheck to save you the time and hassle. fastlane will review your app for the most common causes of rejection 👍.

For example, we’ll check your metadata to ensure it follows iOS app store rules such as:

  1. No other platforms are mentioned in the description
  2. There are no curse words in your copy
  3. No placeholder text is left
  4. No URLs are broken

If we detect any issues, we’ll flag them for you so you can resolve them before you submit your app to the app store. And since fastlane can automatically download your app’s metadata, this whole process takes only seconds!

fastlane precheck in action

More exciting things ahead

fastlane precheck is the first new tool we’ve added to our app automation toolkit since joining Google - and we have even more exciting updates planned! Now that we’ve settled into our new home, we can’t wait to move fastlane forward with our passionate community of iOS and Android developers.

In the meantime, install fastlane or update your version of fastlane (just run 'fastlane update_fastlane') to try precheck and submit your app with confidence and peace of mind 🚀.

Fabric lands top spots for app analytics, stability, and monetization

by Annum Munir, Product Marketing Manager

Fabric is #1 for app analytics, stability, and monetization

About a year ago, we were thrilled that Fabric’s stability solution, Crashlytics, was ranked the #1 most implemented performance SDK by SourceDNA. Shortly afterwards, SourceDNA also named our analytics offering, Answers, the #1 most implemented mobile analytics SDK on iOS! Since then, we’ve rolled out new features like out-of-memory (OOM) reporting to extend stability coverage, activity segments to give you insight into user retention, and unveiled a growth dashboard to provide a real-time snapshot of app growth.

As 2016 comes to a close, we’re excited to share that Fabric has once again earned top honors in stability, app analytics, and now: monetization.

A few days ago, an up-and-coming mobile intelligence startup, MightySignal, released a report highlighting the most-used SDKs across millions of mobile apps. We were delighted and humbled to be recognized in the following categories for the top 200 free iOS apps:

  • Fabric’s Crashlytics is the #1 stability SDK
  • Fabric’s Answers is the #1 analytics SDK
  • Fabric’s MoPub kit is the #2 monetization SDK

With Fabric, we symbolicate over 1000 crashes per second to help customers identify, prioritize, and resolve stability issues that have the biggest impact on their app quality. Thank you for continuing to trust us to improve your app experience!

Last year, Fabric’s Answers was distilling data from 150 billion app sessions every month to help you understand your users. Now, we’re processing over 310 billion sessions every month

As we’ve scaled, we’ve loved hearing from our customers about how insights from Fabric’s dashboard helps them engage and retain users.

Time is precious as an indie dev, and Fabric gives me high level user metrics with no extra work on my part. Now I know when retention is a problem in my apps.


Finally, MightySignal’s data also shows that Fabric’s monetization solution is the second most widely implemented monetization SDK - trusted by many of the top 200 apps to turn their app into a thriving business.

We launched Fabric in 2014 as a suite of tools to help developers build the best apps. We’re excited to have grown to become the most trusted platform for app stability, analytics, and monetization in the world. In 2017, we’re looking forward to building and expanding on this platform to supercharge app development teams.


On a final note, we wanted to thank our customers for your incredible support and feedback. Every day, your passion, innovation, and hard work inspire us. Our mission is to make it easy to build apps, understand users, and grow your business - and we can’t wait to work with you to make Fabric even better in the New Year!


Check out MightySignal’s full report of the top SDKs here.

Launching Answers growth dashboard: understand your app’s growth

by Steve Wilber, Product Manager

In the mobile industry, the adage “if you’re not growing, you’re shrinking” is as true as ever. Today, there are more than 2 million apps available in the app stores, meaning that competition is fierce and growth isn’t easy. In fact, 13 of the top apps in the U.S. saw their growth rate decline by ~20% this year. Mobile teams know that they cannot simply build an app and expect users to flock to it - they need to actively monitor and grow their users.

To help mobile teams understand their user growth, we’re announcing a new growth analytics dashboard. With this new dashboard, you can answer important questions like: “How many new users did my app gain this week vs. the last? Are they completing key actions inside my app? Are they sharing my app with their friends?”

Understand your user growth in real-time

It’s important for product managers and app marketers to stay on top of their new users count everyday and measure their progress each week. That’s why the new growth dashboard features three key data points at the very top:

  • cumulative number of new users today
  • new users count at this same time last week
  • percentage change based on today’s count versus last week’s

By combining this data, your dashboard gives you an instant snapshot of how your app has been growing today and how well you’re performing comparing to the same point last week. It also helps you understand your growth trend for the week and whether you’re improving overall on a weekly basis!

Know the quality of your new users

The key to sustainable growth is not just getting new users, but ensuring they are taking meaningful actions in your app. With the new growth dashboard, you can now see the percentage of new users who performed a key performance indicator (KPI) each day. This helps you measure how engaged your new users are and see if your daily marketing efforts are attracting one-time users or highly engaged users.

Highly engaged users will come back to your app more often, so another way to gauge user quality is to look at your new user retention. The new growth dashboard helps you keep tabs on the percentage of new users that came back to your app after a day, a week and 30 days of installing your app. If the retention rate on a given day is higher or lower than expected vs. the week before, we’ll call this to your attention. This way you can address any issues quickly if there are any!

From our friends at Ticketmaster:

We believe that winners like scoreboards, and this new growth dashboard has been our favorite scoreboard for our mobile app development and QA teams. Retention is a valuable metric that is less sensitive to concert on-sale dates and the growth dashboard has provided us with several new metrics for us to follow how our fans are engaging with our apps in real-time.



Measure and optimize your organic viral growth

For many mobile-driven businesses, in-app referrals can be one of the most effective channels for user growth. Studies have shown that up to 50% of all buying decisions are a result of word-of-mouth referrals. To help you measure your app’s virality, the new growth dashboard shows you how many users are sharing your app’s content or inviting their friends to download your app. One big question remains though: Are their friends actually installing your app from those invites?

The new growth dashboard gives you the answer via its viral installs graph. Powered by Branch (a multi-channel, deep linking and attribution tool), the viral installs chart shows you how many installs came from the invites sent or content shared by your users with their friends. It also gives you the power to drill into which channel is more successful so you can double down on the one that gives you the highest return.

Your command center for growth in 2017

We’ve built this new dashboard to help you understand your user growth and know where to invest your marketing efforts. With 2017 on the horizon, we hope this dashboard will empower you and your team to march into the new year stronger than ever. Here’s to next year!

Building an energy-efficient analytics SDK for iOS

By Stephen Panaro, Software Engineer

The primary goal of any analytics SDK is to gather accurate data. Answers goes a step further by putting an equal focus on timeliness. Correct analytics are one thing, but tracking them in real-time is a super power. Is your latest release stable and well-adopted? Is your 24-hour sale driving more purchases? We’ll give you the answer immediately so you can take appropriate action. To deliver this real-time insight, we have to pay special attention to how we design Answers for iOS, tvOS, and macOS.

Low power as a feature

We could have built Answers to make a network request for every app event as it happens. This would have been the most timely SDK, but it would have also drained battery life. Or, we could have designed Answers to collect large batches of events and sacrifice all timeliness for great battery life. Instead, we took a balanced approach in between these two extremes. It has served Answers well, but we wanted to revisit our implementation to see how much better we could make it.

With Answers 1.3 for Apple platforms, we introduced several new power optimizations throughout the SDK. We prioritized application performance and user battery life while keeping latency as low as we could. In some cases, these optimizations produced significant power gains. This allowed us to have a large impact on battery life with a negligible aggregate impact on Answers’ latency. In the next section, we’ll walk through some of the improvements we made to enable these gains.

Limit networking

First, we turned our focus to Answers’ networking. Networking can have a substantial power impact, which made it a great place to look for optimizations. A simple way to reduce its impact is by limiting the number of requests you make. Answers has always done this by sending data in batches. For our latest release, we try even harder to ensure that app events that occur close in time to each other are sent in the same batch. This is most beneficial for heavy users of Answers Events, especially when events are logged in bursts. We also tuned our retry policy to help prevent us from making requests that are unlikely to succeed.

Background uploads

It’s impossible to talk about power-efficient networking without mentioning NSURLSession’s background uploading capability. We’ve used this capability for several years in crash reporting and seen really good power and reliability wins, so we wanted to bring those to Answers. Unfortunately, we found some issues with the background uploading API in iOS 10. Because of that, it is currently only suitable for extremely low volume networking. We hope to enable it in a future release when these issues have been addressed.

Low power mode

Next, we took advantage of NSProcessInfo’s lowPowerModeEnabled property, which notifies apps when a device enters low power mode. Introduced in iOS 9, this is a very strong indication that the user wants battery life to be maximized. When devices are in low power mode, Answers retries network requests less frequently. On macOS, we take similar action when thermal conditions are elevated. This is an easy way to further reduce our power impact, and is particularly effective when networking conditions are poor. We also have plans to expand our adoption of low power mode to other parts of the SDK.

Quality of service

In addition to the low power mode API, we also adopted two easy to use APIs to better inform the OS of the priority of Answers’ work. First, we made sure to set the qualityOfService property of our NSOperationQueues. This was a one-line change and makes sure that Answers always defers to your app’s needs. We also made extensive use of NSProcessInfo’s activity APIs to help the OS understand what we’re doing and how our work should be prioritized. As an added benefit, this makes it more obvious what Answers’ threads are doing if you happen to catch them in a debugger.

Optimized timers

Finally, we wanted to improve our usage of timers. Answers has always relied on timers because we have to make sure we periodically relay any events back to our system. In this release, we updated our timers to fire less frequently. We also now choose a timer’s tolerance value based on its duration to help the OS schedule work more efficiently. On macOS, we’ve adopted NSBackgroundActivityScheduler. This is similar to a timer but takes into account even more system conditions when scheduling work. We discovered this API while reading Apple’s Energy Efficiency guidelines, which has many other useful tips.

Same Answers, more battery

When we started to plan for Answers 1.3, we knew improving energy efficiency and satisfying Answers’ design goals would be challenging. Being accurate and being real-time are inherently power-hungry, but they’re essential to Answers so we were determined to find a solution.

We stepped back, took a holistic look at Answers and identified our best opportunities for improvement. Fortunately, there was a large overlap between the problems we wanted to solve and the problems that Apple supplies a solution for as a part of iOS. This was fantastic on two fronts: it let us write less code and in many cases, it unlocked optimizations that wouldn’t be possible otherwise.

We’re thrilled with how this approach turned out and are even more excited to share these changes with you in the latest Answers release. We hope that this makes it easier for you to build the best apps with the lowest impact on your users’ battery.

If you’re interested in further reducing your app’s impact on battery life, we encourage you to incorporate these best practices into your development workflow. Most are simple to learn and implement and the more apps that adopt them, the greater impact they will have. Plus, no one wants their app to be at the top of the battery section as the worst offender in Settings!

Introducing OOM reporting: a new dimension to app quality

by Sean Curran, Software Engineer

Stability issues can derail the success of even the best apps – glitchy software repels people. We know that app quality is one of your top priorities and crashes are your worst nightmare, which is why Crashlytics will always alert you when issues arise. We’ll even help you pinpoint their root cause so you can fix issues fast – we’ve got your back!

Today, we’re extending our crash coverage to include out-of-memory (OOM) reporting on iOS. Now, you can see stability from a whole new angle by understanding the impact OOM events have on your app experience.

What’s an OOM event and when does it occur?

Unexpected app terminations degrade your app experience and interrupt your user’s session. One type of app termination you’re probably familiar with is crashes, but there’s another unexpected termination that warrants your attention called an OOM event.

An OOM event is an app termination that occurs when a mobile device runs out of memory. All apps need memory to work, but there is only a finite amount available on each device. When an app needs more memory and there isn’t any available, the operating system terminates the app session. To your users, this looks like any other crash, however in reality, this is an OOM event.

Our approach to solving a hard problem: intelligent heuristics

OOM events are difficult to report because iOS doesn’t provide any direct mechanism to detect them and they can be caused by factors beyond your app environment and control, such as your app’s memory usage. But because of how important it is to understand your rate of OOM events, we took on this challenge and added OOM reporting to Crashlytics for iOS devices.

Here’s how it works: When you enable the Crashlytics and Answers Kits available on Fabric, we get a stream of live data about your app’s performance. Then, we apply a server-side process of elimination to this data stream to detect OOM events in your app. This detection is based on an intelligent heuristic, inspired by the work of two talented engineers. In other words, we analyze your app’s event stream to come up with an explanation of why it terminated and if we can’t match it up it to a known reason for termination, we count it as an OOM event. And, since no changes to the Answers SDK were required, you will automatically get OOM reporting without needing to do any work (as long as you have both Crashlytics and Answers installed).

This is an example of how your app analytics and stability kits can work together to unlock powerful new insight – something neither kit could do alone.

At Pinterest, we're shipping iOS app updates every two weeks to millions of people. Using the new OOM insights, we've been able to track our memory optimizations and have confidence in the stability of each release.

- Scott Goodson, Head of Core Experience


New line of sight into the impact of OOM events on app quality

Our new OOM reporting dashboard will help you understand if OOM events are a problem for your app. Now, you’ll be able to see the overall percentage of app sessions that were unaffected by OOM events across your builds. You can even drill down and see the percentage of OOM-free sessions for individual builds. This will help you answer important questions like, “Is my app being terminated more on one build than another?” and “Is my app seeing more or less OOM-free sessions over the last week?”

We’ll also give you a sortable, daily device breakdown so you can compare the raw OOM counts and the percent of OOM-free sessions across different iOS devices. Once you know which iOS device experiences the most OOM events, you can better triage and spend your time investigating problems on your most used devices. After you roll out a fix, you can monitor the number of OOM events on that device to see if your solution helped reduce them. You may even learn that there are some low-end devices that you simply can’t support.

This additional information paints a clearer picture of your app stability across devices and provides clues for troubleshooting.

Finally, we’ll show you the total number (i.e., the raw counts) of OOM events across all of your builds versus your top three builds. Use this graph to understand the prevalence and magnitude of OOM events.

Don’t let OOM events crash your app party 🎉

Our mission is to ensure that there are no more sad, unstable apps. By adding OOM reporting into Crashlytics, we’re giving you even more insight into the quality of your app. Don’t be blindsided by OOM issues that disrupt your users’ app experiences (and maybe even cause them to flee!). Monitor your OOM-free sessions, promptly identify when OOM events become a problem, and get valuable direction on where to start your troubleshooting by going to the OOMs page from your Crashlytics dashboard. Check it out and let us know what you think!

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