New Features and improvement in Android M Preview 2

 STABILITY,PERFORMANE AND BATTERY LIFE

• It has to be said that, even from day one, Android M’s stability was considerably better than we saw with L. This makes sense considering Lollipop was a big departure from KitKat, while M is more a minor evolution of what was started with Lollipop. With the new preview, stability only gets better
• Android M is shaping up to be a very stable, efficient build and should hopefully have considerably less bugs and other day-one issues than we saw with Lollipop. Considering Lollipop still is riddled with bugs and performance issues, we are really excited to see that M is taking a step forward here.

MEMORY MANAGER UI GETS REWORKED

(i)One of the changes found in the original M Preview was an improved memory manager that added several new features including a way to better see how much RAM each of your apps was using.

(ii) Finding the setting in M originally required you to take several steps, but in Preview 2 it is more prominently found in its own “Memory” tab right in the Settings screen. Beyond that, the UI has also been cleaned up considerably making it much more pleasant to use than before.

DELETING SCREENSHOTS FROM WITHIN NOTIFICATION TRAY

Each time you take a screenshot in Android (4.0 and higher), you’ll get a notification in your tray letting you know it has been saved. With Android M Developer Preview 2, however, there’s now also an easy way to delete them as well.

NO MORE DARK THEME

(i) The new (optional) dark theme in Android M was one of the first things we noticed when diving into the developer options for the test build. It was nice to finally have another option aside from the very bright standard UI. Unfortunately, it is no longer present in the second preview.

(ii) The removal of the feature just goes to show you that test builds don’t always give an accurate picture of what to expect from final software. Is the dark theme gone forever? Hard to say. It’s possible that they were merely testing it and decided it wasn’t worth keeping. Or dark theme might not be fully ready for prime time and was removed in preview 2 to further fix it up for a final release. Only time will tell for sure.