Does it support torrents with files bigger than 4GB?
Yes, but the FAT32 file system has this limitation. The app checks for the file system and if it is FAT32, the limit is applied. You can download torrents bigger than 4GB, but the biggest file in the torrent can not be bigger than 4GB. If you want to download files bigger than 4GB, you will need a different file system, exfat for example.
Does the app use the internal flash at all when configured to store torrents (both index and files) in a USB drive or external SD card?
It uses the internal flash if its private directory is located there to store the fastresume files, and the list of torrents.
I cannot write to my external sdcard, however I have Android 5.0(Lollipop). How can I enable writing to external sdcards?
From version 1.5.2 tTorrent supports writing external (at least Lollipop is required), but only if the permission is granted in the settings. You can grant the permission at Settings/Directories/External storage access, you have to pick the root folder of your scard. Please note this process should be repeated if you insert another sdcard.
My device has Android 4.4(KitKat), and I cannot download to my external sdcard. I get a permission denied error. Why?
This is a problem with Android 4.4, not the app. The KitKat system denies write access to the external sdcard. See these links for further information: https://groups.google.com/forum/#!msg/android-platform/14VUiIgwUjY/UsxMYwu02z0J http://android.stackexchange.com/questions/58592/using-an-external-sdcard-with-kitkat The workaround for rooted devices: http://trendblog.net/fix-kitkat-sd-card-write-restriction or https://play.google.com/store/apps/details?id=nextapp.sdfix Workaround for non-rooted devices: Create the directory /Android/data/hu.tagsoft.ttorrent.lite or /Android/data/hu.tagsoft.ttorrent.noads on the sdcard, depending on your app version, and select this directory as the save path. Please note that the files downloaded to this location will be removed if you uninstall the app.