On screen electronic timer 4 custom puzzles

There are on-screen timers for all of the puzzle solving on chess.com, save for the custom learning section-the one I use the most. I've looked through all my settings and available tools on here, and I cannot find an option to use a virtual timer on my screen for those problems. Does anyone know if there is such a tool available on chess.com, and if not, is there an application in the Google Play Store that might be compatible with the chess.com application (automatically stops and starts after you solve and go on to the next puzzle, for example)? I really need to get my time down solving tactics, and that's hard to do when you're not paying attention to how long you're actually taking on different themes Etc

Thanks a bunch in advance