What are /r/SummerOfUs' favorite Products & Services?

From 3.5 billion Reddit comments

First of all, pick the one you're the most interested in or use the most, so you'll be happier making something for it.

If you're still undecided, I'd recommend the web. Why?

• It's the most portable. You'd be hard pressed to find many devices these days without some sort of browser. This makes it easier to show off to your friends, even if they don't have a windows/android device.
• Learning networking is built in. While it's definitely possible to learn networking on other platforms, on the web having a basic understanding will help you with even just displaying text on a page. You'll probably understand servers vs. clients better this way.
• Most android programmers I know (I'm assuming windows too) use something like Android Studio, which isn't bad, but when you're just starting out can kind of hide the fact that behind the scenes you're just editing text files.
• On the web, you can make anything from a personal site with just your name on it to a full-fledged app, and that flexibility lets you define your own learning curve.

If you're averse to PHP, then like OP said, Python is a great choice for beginners. There are lots of web frameworks for it, and one I'd recommend is Flask. However, building what you want to make in PHP is far better than not building it at all. Hope this helps!