thirst content: content that is very sexual in nature without necessarily becoming straight up nudity or pornography, something platforms like Instagram or Twitch are famous for. For young people being unnecessarily horny is often referred to as being "thirsty." As in "thirsting" after someone you find attractive.

image browsing apps: Instagram could be described as an "image browsing app," and as such this user is looking for apps that mirror Instagram/Twitter/Pinterest content without actually having to use those services.