I like your image work very much. I'm a Web programmer, but also like to do simple image edits.
I have an IPad 2 A1395 ~2011 with 16GB of memory.
I do screen prints of the TSTO game, then edit these pictures on my iPad and upload them to the Images folder. The image editor app I use is a free app called "Photo Editor-" by Axiem System. It doesn't have very many feature I use because it is for making real world picture look better. I basically only use the following three features:
Crop: To get just part of a picture to make the image smaller and more focused on a topic.
Text: To write a comment on a picture.
Draw: To circle or point to something in a picture.
The other features like red eye elimination aren't needed to edit TSTO game images.
I would like an editor that can do the following type of operations and I thought you might know of an iPad app that might be a good choice:
Transparent Alpha channel: To make the background show throught parts of picture.
Border Draw tool: Allow you to draw a boarder, ie square, circle, multi-point area, etc.
Paint Can Tool: Fill border with a color
Select A Boarder: Allow you to select a color, ie black, and use that as a boarder to fill it with a Paint Can tool
Save as: Allow you to save to jpeg, png, gif, etc...
Cut/Paste: Allow cutting and pasting from two or more images.
I'm used to using Windows image editor software like PaintBrush, Gimp, IGrafx Image/Micrografx Picture Publisher(Doesn't work on Win8/10 so I can't use it anymore).
Apologies for the very late reply; unfortunately I cannot help you.
The images you're seeing are from the files themselves, so I don't have do to anything to them, at most they require cropping, but that's very rare to happen and it's done in my notebook.
For the apps question, I honestly have no idea since I use Android and even then anything editing that needs to be done is not done there.
uhm... well, I'm not going to lie to you, I've completely forgot about this thus the very late reply, sorry about that.
If you mean the Category:Character Unlock Images, then those are from the files, if you're talking about the notification messages or the Category:Unlock Screens, those are screencaps, and are edited, or cropped more accurately, but again, the amount of work there is just minimal.