Friday, September 26, 2014

When Should I Drop Support for Android 2.3 and iOS 5?

My previous company, Logos Bible Software (recently renamed to Faithlife Corporation), has just dropped support for Android 2.3 Gingerbread for their suite of mobile apps and will soon be dropping support for iOS 5 for their iOS suite. This caused a few minor complaints on the Android side, but for the most part people understood that their device was too old to be supported. On the iOS side, there are many users still using the original iPad which runs iOS 5 and they are experiencing some crashes due to the iPad 1 not having enough memory to handle the needs of the Logos apps. Obviously the ideal situation is to leave those users with a version of the app that performs well on their device, but at this point is it worth the extra developer hours to fix a problem that only exists for a small percentage of users on a soon-to-be obsolete device? It's a tricky problem.

Thinking about that problem led me to muse on how an app can get to this point in the first place. When should a developer drop support for an older operating system? This applies to desktop software programs as well, but the pace of desktop operating systems changing is so much slower than mobile, I don't think it's as big an issue.

The choices

There are two main approaches I can think of:

1) You could set a hard and fast rule that you drop support for an operating system version when the percentage of users running that version drops below 5% (or some other arbitrary number).

2) Pick a cut off date and drop support for the operating system version on that date, regardless of how many users remain on that platform.

Issues with the first approach

If you insist on waiting until the user base drops below some percentage, the main problem is who knows when that will happen? At the time of this writing, Android 2.3 still has over 11% of the total Android marketshare. It could be quite a while longer before it drops below 5%. Additionally, if that's the only criteria, it's easy to see how performance could start to degrade on older devices because if there's one thing you should know about developers, it's this: Developers like having the newest stuff. They run the beta version. They upgrade their devices as soon as they can convince their spouse they "need" a new phone "for work". Developers are testing their code on that top shelf, speed demon device they love, not the $50 bargain bin smartphone your parents picked up to go with their Walmart family plan. Now don't get me wrong, this is the fault of the developers. They should be testing on those devices FIRST, instead of not at all. But that's not fun, and unfortunately, many devs won't do it. So by the time an OS version drops below the magic percentage, the app might be so fragile on that platform that it's unusable anyway.

Issues with the second approach

From a developer's perspective, it feels a bit weird to release a new version of an app that drops support for iOS 5 or Android 2.3 (etc) without any real reason other than "we want to leave those users with a stable version". Granted, that's an admirable goal, but "this new release adds five new features!" and it's not necessarily unstable/unusable, so it feels like you're cheating those users out of the new features and fixes. The instability creeps in over time and is hard to notice until it's already too late. Objectively speaking, this option is probably preferable to the first choice, but when it comes time to actually make that call, it leaves both users and developers unhappy.

Other options?

What else is there? Maybe Apple has the right idea. They say that developers should support the "current version and the current version - 1" (I tried really hard to find a source for this, but had no luck. Pretty sure it was a slide in a WWDC presentation). That probably works on iOS and OS X where most users update to the new version right away (if their hardware supports it), but it's not really feasible on Android or Windows.

I'd be interested in hearing other people's thoughts. I don't know what the right answer is, but it's definitely a tough problem and one that is important to get right to avoid leaving a bad taste in the mouths of users.

Sunday, August 24, 2014

Why you should worry about the size of your Android app

My phone has 8GB of storage. Well, really 5.67GB once you account for the space the Android operating system takes up. Apps take up the vast majority of that space and I constantly find myself having to uninstall a game or two in order to have space on my phone to install the next game I want to play or app I want to use.

I find that being in this situation makes me pay much closer attention to the size of apps when browsing Google Play. If I'm going to install an app, it needs to provide enough value to be worth taking up space on my phone; the bigger the app, the more value it must provide to me.

Google, in fact, seems to agree with me. They've said on numerous occasions that smaller Android apps (also called "APKs") get installed more and uninstalled less. Consequently, making your app smaller could result in a boost in your Google Play search rankings, and increase your retention rate.

Remove third party libraries

Do you really need that third party library that gives you support for 100 different ViewPager indicator styles? Or could you get away with pulling out the one style you want to use and including it in your project directly? Reducing library dependencies is probably the biggest win you can get when trying to reduce app size.

But it might not be easy. It may take some time to pull out the pieces you need, and you may make a mistake or inadvertently introduce some new bugs. High cost & risk, high reward.


Proguard shrinks your app size by removing any unused methods and classes. It also makes your app harder to reverse engineer by renaming your methods from something like void sendPasswordToServer(String password) to void a(String b). You can imagine how this also makes your app smaller.

If you're starting a new app, enable Proguard in your build right now. Seriously, go do it. Proguard is super easy to set up for a new app...the more code and libraries you add, the trickier it gets to add Proguard and be sure nothing will break. Five minutes of integration work now could save you major headaches later.

Shrink those images!

Image files take up much more space than text files, so ideally, you won't have many of them in your app. On the other hand, apps that include a lot of visual content are much more pleasant to use than staring at a wall of text. So what can you do?

Enter ImageOptim, a free program for Mac OS X that reduces the size of your images by removing unnecessary metadata and other tricky optimizations. (If you're on Windows, you could try PNGGauntlet, which I've heard works well, but I haven't used myself).

When I receive an image from one of our designers, I always run it through ImageOptim before adding it to an app (Android OR iOS). I frequently see size reductions of over 95%. If you haven't been doing this, try running all your images through the optimizer and you might be surprised at how much space you can save.

Overall, reducing app size helps you, as a developer, get your app installed by more users and it helps your users by being respectful of the limited amount of space they have on their mobile devices. It's really a win-win situation, so it's something that developers should constantly keep in mind.