Lack of updates on most devices, xml to define interfaces, fake java as its primary development language, messy file hierarchy, obnoxious issue wherein apps cannot be given access to entire SD card meaning you can't just have a pictures or ebook folder and have more than one app have access to said folder.
Example annoyance third party gallery app can't delete photos created by other photo app. Alternatively calibre companion can't access the same hierarchy as ebook readers.
Until recently the offline map support was crap I think this has improved but as I already have Navigon for $30 to have this basic feature so I haven't verified this.
If you don't reboot it regularly it generally becomes unusable due to memory leaks eventually.
It crashes for no discernable reason on occasion usually when I'm not even using it surprise reboot!
The obnoxious need to hack your own device to have full control of it.
As an Android user my next phone will be a dumb phone plus laptop.
