Spirit FM Radio radio app that doesn’t require internet connection as it doesn’t act in streaming, it just requires bluetooth enables. For 2.1 or greater, in many cases requires root access
ColorNote notepad app. Widget support and protected notes
Bluetooth File Transfer app that allows to send files via bluetooth
GO Backup backup/restore contacts, messages and apps (this last requires superuser rights)
Better Battery Stats extensive info about battery usage, useful to understand how much battery is used by processes
Total Commander the famous file manager now also for Android
imo multi instant messaging client
Copilot GPS free navigator with offline maps, it doesn’t have 3d view and vocal
GPS Status useful to know own coordinates, it also allows to fix GPS signal in case of issues
App 2 SD allows to move apps to SD