I'm running synergy-android (0.0005) as a client on an HP Touchpad running CM10 and a Galaxy Note running rooted stock 4.1.2 with a Windows 7 host.
Several characters do not get entered on the clients when typed on the server's keyboard:
[]{}|;:'"`~
(This is not an exhaustive list, but I'm using a US qwerty layout and therefore this is the low-hanging fruit.)
Ñ/ñ is missing as well for spanish speakers, accents (áéíóú) as well. Even after getting correct keyboard layout mapping on device.