How can I make a more efficient way of saving?

I have made a mobile version of my Planet Clicker, to run in the form of an app. I have made a system that saves the game every 15 seconds, saves the JSON as a Dictionary Value, then saves the Dictionary as JSON to Local Storage. However, after a little bit, the save takes around 10 seconds and freezes the UI (Music isn't affected), and on my iPhone 13 Mini that I sideloaded the IPA to, it even crashes. Is there a more efficient way to save the game for mobile?

I needed to change it to 15 seconds, it was originally 2, but that was way too much for it to bear. I want it to be like a normal app that progress is typically saved instantly, or more so just stored on the device plain.

I also need to use the `Save Game to Slot "xxx"` because my game is full of persistent objects.

If you want a more efficient save, you'll need to consider and define only what you absolutely need to save, and do so manually. If it's still taking too long, you might consider changing the format and contents of the data you're saving to something smaller or more simple. Depends on your game really.

Thanks for the response! I didn't think about it, but I guess that would be the problem. However, I instead made an array as well as a backed up all of my variables to the dictionary, and saved them both to local storage as JSON, and I feel like it works better this way. There was always a very short, but somewhat noticeable stutter when system saving across every game I've made, so I set it to 15 seconds, but now I can have it save every 1 second without any noticeable problems.