It's 2018, and the Spotify app still has several internal issues that negativily impact the app's usability, performance, and just internal workings. The app still targets Android 6.0 Marshmallow, a release of Android from 2015. We're now into March 2018, and Android is up to version 8.1, with Android 9.0 just around the corner (a developer preview is already available). The app should be targeting SDK level 27 (Oreo 8.1, or Oreo MR1, if you will), not API level 23. The app also still has Android 4.0.3 as it's minimum supported Android version, which along with 4.0.4, only has 0.4% total market saturation across all Android versions tracked by the Android Developers Dashboard. I feel that that should be bumped up to at minimum Android KitKat (Android 4.4, or API level 19). It's not difficult to update the build.gradle files to target SDK level 27, and drop support for older Android versions that aren't used that much anymore, as it actually costs more money to maintain compatibility with older Android versions as old as 4.0.3. Dropping support for older Android versions will actually reduce development costs, something that's kind of important for Spotify as a company I'd imagine.

Onto another point now: like I mentioned in my previous thread, Spotify still doesn't properly support 18:9 displays without the override some OEMs implement into their custom software made for their devices, like Samsung's Samsung Experience and OnePlus' OxygenOS. Some OEMs don't implement that override, like Google (the developer of Android). Google completely avoided the implementation of an override for apps that doesn't properly support 18:9 displays in AOSP and the official software for the Pixel 2 XL on purpose in the hopes that developers and companies would actually implement the support for it in their apps, and some companies have failed to do so, including Spotify. So please, Spotify, optimize for taller displays that aren't the 16:9 aspect ratio.

One last point: Spotify still only uses 32-bit APKs, as visible in the version number in Spotify settings. (armv7 is 32-bit). While Spotify performs really well on modern flagships like the OnePlus 5T, Samsung Galaxy S8/S8+, and newer devices even without proper 64-bit support, the app could probably perform even better than they do now if Spotify started targeting the 64-bit architecture instead of still only primarily targeting armv7.

Also, everything I've mentioned is going to be enforced by Google, such as the 64-bit requirement and the target newer SDK requirement. That's primairly why I'm bringing up the issues. It's not that hard to update libraries, target a newer Android version, and drop support for older Android versions. This is really important. Android is the most popular operating system in the world, and as such I think Spotify should give the app internals a bit more care and attention.