Is it possible to deactivate the default mail-client Mail / Gmail? I do not need it, I will use K-9, which is not installed at the moment. With my last installations I put these 2 apps in quarantaine with Titanium Backup, but for a while I do not want to put anything in quarantaine, because I am searching for a hard to understand wifi-problem. Maybe it's gone. Since a complete new install I din't notice it, but it is too early to be sure. The tablet has to be in standbye for a longer time, to test it.