1. What, exactly, are you trying to do with the cell? If I tap on a cell, I'm able to edit the cell from the location where I tapped.
2. To add a cell to the end without a keyboard, you need to select the insertion point at the end, and then use one of the buttons at the bottom of the screen to create a new cell.
3. I don't understand the problem here. Can you explain?

Wolfram Player supports (most) dynamic content in notebooks, but it does not support editing notebooks.

What makes editing so difficult? What are you trying to accomplish that you were unable to do in the app?

When you tap an insertion point at the beginning, middle, or end of a notebook, you should see a view at the bottom of the screen that looks like this (the important part is circled in red):

You then tap "Input cell" or "New cell" to insert a new cell at the insertion point. If you do not see those buttons, and you are editing a Wolfram notebook, then I'd like to request that you share the notebook with me so we can investigate why they didn't show up. Thanks!

Thank you! I was able to reproduce the problem, and I am investigating.

I posted my question about the Wolfram Cloud App on this forum because it was suggested to me by Wolfram Technical Support when I reported the issue to them in a chat session. After I was unable to find any resolution here, I emailed Wolfram Technical Support and they have been able to reproduce the problem. They have now reported it to the developers of the App.

The only workaround they were able to offer is to download the file locally, make the edits, and then re-upload it to the cloud. This would not be convenient for me so I’m going to delete the App from my iPad and use Wolfram Online on those occasions when I don’t have access to my PC or Laptop.

Thank you to anyone who has taken an interest in this topic.

Thanks for pressing the question, Ronald. I gave up on the iPad app years ago... must be a retired-guy thing. My take was that there is a gap between what you and I assumed the usage scenario to be and what the developers assumed it would be. Overall, I think all of us are in a transitional period from iPad as toy (and I would include some Mac apps in that class) to iPad as tool. Apple itself is transitioning from commercial to proprietary processors, so we should expect a rugged landscape for a while.