Tested tablet Skyworth T065, but there was authorize problem with Google account, and therefore does not synchronize email, will not connect to Google. I looked into the tablet files, and there is a file /etc/hosts which had redirection:
74.125.93.113 android.clients.google.com 127.0.0.1 localhost
A android.clients.google.com IP address has changed, so authorization is not where it should be. Remove the first row, left alone:
127.0.0.1 localhost
Restarted the tablet and authorization started to work.