So I buy a very cheap Bluetooth keyboard to take advantage of shortcuts and make things faster as well, but in my tests and verification for my surprise only inside TVPaint the "CTRL" key does not work properly, inside other Apps such Google Chrome, Text Editor the CTRL key works fine.
So I make another test on my cellphone and the results were exactly the same, unfortunately.
If I go to the shortcut options and press the CTRL the key recognizable by the App is "`" booth on my Samsung Galaxy and my Xiaomi cellphone, also, it's the same as the "Esq" key the TVPaint understand "`"
Another test inside TVPaint Android App, if I try to save the file, select the name holding shift and press "CTRL" the name just erase like a delete key.
I don't think it's a bug or anything, I believe the developer just make a little mistake or didn't think about the integration of an external keyboard for Android devices.
More tech information about the devices used to help improve the App, both have the same issue.
Samsung Galaxy Tab Pro 12.2 3G
OS Android 5.0.2, TouchWiz UI
Chipset Exynos 5420 Octa (28 nm)
CPU Octa-core (4x1.9 GHz Cortex-A15 & 4x1.3 GHz Cortex-A7)
GPU Mali-T628 MP6
Xiaomi Redmi Note 7
OS Android 10
Chipset Qualcomm SDM660 Snapdragon 660 (14 nm)
CPU Octa-core (4x2.2 GHz Kryo 260 Gold & 4x1.8 GHz Kryo 260 Silver)
GPU Adreno 512