Whenever you wipe your phone or get a new one and when you redownload your apps, you’ll basically have to reconfigure everything again. This can be a bit tedious especially if you have everything set up a particular way and it’ll probably take your hours to get everything back to the way it was.
Thankfully that should no longer be the case with Android M. It seems that one of the features that users can expect from Android M is the ability to automatically backup your app data onto Google Drive, with up to 25MB of app data being allocated per app. This means that unless you somehow have app data more than 25MB, pretty much everything should be backed up.
The best part is also that this will require no new code from developers as it is a part of Android M’s features, so once Android M rolls out, you can expect your apps to automatically backup its data without having to worry about whether the developer has bothered to implement that feature.
However at the same time, it seems that developers have the option of opting out of the automatic backup feature for whatever reason. Some app developers will also need to write code specifically if there are specific portions of the app data that aren’t being backed up if it isn’t recognized by Android M, but other than that if you’re a loyal Android user, moving from phone to phone should be an easier process.