Note, of course, that your device's font may not support all known characters. Characters that your device cannot render will most likely show up as empty rectangles.
HTC Vision / T-Mobile G2 users: I assigned Charmap to one of my "Quick Keys" and it works pretty well. :)
Charmap is ad-free, Open Source, and licensed under the liberal MIT License. Don't hesitate to email me with comments or suggestions.
Free as in beer, no spying, no adds, no in-app purchases :-)
You can browse the full Unicode range, jump to Unicode code points or blocks of your choice, or search in character names and Unihan description.
For all characters you get the standard information in the Unicode Character Database (UCD) and for Kanji characters you get all the info in the Unihan database.
Full support for characters beyond Basic Multilingual Plane (BMP) and Emoji (including the color Emoji starting with Android 4.3).
Please let me know what you like / don’t like / would like.