Hmm???
Indeed though I’ve done no testing on Android N yet or anything with Jack. A tremendous amount of inefficiency and bugs in the Android Java implementation is due to the adoption of Apache Harmony which was quite weak in many areas. Sadly Google just poked and pecked at things very slowly after much developer outcry spread across many OS releases. There may be some hope with Android N with a switch to OpenJDK / Jack, etc. etc. for better out of the box performance, but if you need to support a wide range of OS versions performance is in your hands. Since day 1 with Android I’ve been using my own collections API which recycles iterators automatically. Another super weak spot which I’m sure still hasn’t been fully addressed is runtime annotation processing. You need to come up with your own caching mechanism otherwise face a ton of generated garbage.