That sounds like you might just have a very slow phone and/or very slow internet. The Imgflip website is generally extremely fast and lightweight compared to most popular sites on the internet. Practically zero third party scripts, and no 3rd party bloat at all.
Clicking on a chat only takes 50ms (basically instantaneous) for the slowest 1% of users on our servers. Anything slower than that is likely from your internet connection.
There are really only two things that provide weight to Imgflip browsing: 1) Images, obviously Imgflip is all about images and there are tons of them, and images take a lot of bandwidth, 2) Advertisements, but only on pages that have ads and only if you are not a Pro user. Ads are slow and crappy but they are a requirement for us to make money. Buy Pro and they go away :)