My problem was downloading so many "might be useful someday" utilities that I couldn't remember what each one did. I decided I didn't really need 6 note taking apps and 4 PDF readers...and that I must resist adding even more to the collection!
As for getting out of the recliner to do work on the iMac...I just downloaded Splashtop 2, and can now run the iMac from my iPad. Laziness is preserved through technology.
Thumbs-up for preserving laziness through tech.
As for not knowing what apps do, I know what you mean. I group mine together by utility so I have a better shot at remembering. Maybe it would be useful if Apple added a feature that allowed you to make a short note about an app, so you could hover over it for a reminder on what it did well or whatever? (That kind of feature might have other uses, like gamers might note game cheats, etc.?)
Even though some apps are meant for overlapping functions, I've found that it's useful to have a few, because one often works better than another, depending on the specific task. I do find replacement apps, though, and I delete if I come across something better.
Recently, I resurrected a browser that lets me view two websites side by side. I had replaced one such app for another, because I thought I wouldn't need two side-by-side browsers. But I started reading Shakespeare's Troilus and Cressida on one side, and kept a character list open on the other, because I needed help tracking of who was who. I was in the middle of reading, and I didn't want to lose my place so I could use the side-by-side viewer for another purpose, so one of my deleted apps got a reprieve. I restored it so I could do the other thing I wanted. So now I've decided to keep both side-by-side browser apps on my iPad 4.
Sometimes, I find uses for apps I didn't anticipate, and I end up happy that I kept them on my screen. I have a bunch of travel apps, for instance, that find services, etc., describe city features, etc. I've found that having several of them is useful, because I want to find stuff on the fly, and they often have strengths and weaknesses, or gaps. Like one app will have good info about one airport or city, but lack equivalent info for another airport or city. I was about to delete one such travel app for another in one case and noticed that the older app features airport ATM locations, which the other app didn't. So I keep both apps for now, because when you need something during a layover, you often need it quickly. Meanwhile, I also emailed the developers of the other app, in hopes that they'll add ATM locations, too.