The motivation of this post is to raise the awareness of a possible problem of Android FTP client programs.
At this point, I am not sure what's the real problem. So I will simply describe what I did and what happened.
I bought a no-brand Android Tablet. It runs Android 4.0.4 with Kernel of 3.0.8. Every thing works great until I begin to work with the FTP. I download every free FTP program that is compatible with my tablet and none of them worked flawlessly. There are times the error is caused by Java.net.SocketTimeoutExceptions. But a lot of times, it simply stopped. They happened pretty much randomly. Almost all programs/apps connect to my server at some point. But none of them can reliably maintain the connection for long enough time. I am not ruling out the wifi connection of the tablet since at times, it does not have the idea connection.
With the same wifi setup, I run the FileZilla on a Windows 7 laptop. Everything works great. No problem what so ever.
Of all of the Android FTP client apps, the most reliable one. At one point, I was able to make couple of download and upload. But, eventually, it hanged. The FTP clients I have tested are: AndFTP, ZealFTP, DroidFtp, AbyssFTP and FtpCafe.