According to the initial screen, connectbot uses an Apache 2 license even 
though it is based on "JTA Telnet/SSH client, provided under the GPLv2 
license". Either the screen is wrong, or "based" means something else, or 
connectbot infringes on the GPLv2. In the latter case, relicensing under the 
GPLv2 seems the easiest option; the GPLv3 and GPLv2 are incompatible with each 
other, and JTA does not seem to be licensed under the GPLv2 "or any later 
version", just under the GPLv2.

Also note that the Apache license and the GPLv2 are incompatible:

http://www.apache.org/licenses/GPL-compatibility.html

I noticed this because of issue 431, since the initial screen in connectbot 
talks about the Apache License but also links to the GPL v3.