Adding a small delay after someone types a letter and before the API is hit would improve it a bit in the meantime. Also use history.replaceState so you don't add so many entries to the browser history.

Every time I type a letter (or each time I hit backspace), the browser fires off a dozen requests for the search term and all the images for every app in the result. This is a waste of bandwidth and bogs the browser down. I'm all for interactivity but you need to take usability into account a bit.