Mobile version of Reddit.com shows this huge popup on nearly every page, trying to convince me to install their app because I deserve the best.
1. It's 50% faster. Okay, sounds good.
2. Infinite scroll. Wait, how is this UX anti-pattern a good thing? Infinite scroll is a great way to lose focus and be frustrated (see the footer of grumpy.website for more info).
3. Autoplay GIFs. What? Guys, seriously…
So, no, I will not install your app, it seems to have one nice thing and two bad things — not a good ratio.
Also, check out the copy on this popup. The huge bright button will bring you to the app store, away from what you came for. Of course, they won't (and can't) remember where you've been when you clicked on it, so after installing an app you won't be able to quickly continue (CONTINUE! right?).
And if you just don't want to be bothered, you have to click on a tiny grey link that "go to the mobile site". I'm already here, I don't have to go anywhere, just get this half-screen panel away, please!
Here is an idea: provide a great experience right off the bat so that I don't dread coming back.