My phone popped up the “Storage Full” warning while I was trying to take a picture of my cat doing something cute. I opened Settings, saw 128 GB was full, and assumed I’d have to delete half my photo library. Then I actually looked at what was using the space.

My photos were using about 40 GB. The other 88 GB was apps I hadn’t opened in years, cached data, saved podcasts, and old text message attachments. I freed up 50 GB without deleting a single photo. Here’s where all that space is hiding.

The usual suspects (in order of space hogs)

1. Old text message threads. Every photo and video anyone has ever sent you in a text is saved on your phone. Go to Settings > General > iPhone Storage > Messages (iPhone) or Messages > Settings > Storage (Android). You will probably find gigabytes of “GIFs your friend sent in 2022.” Delete large attachments — you can filter by size — or set messages to auto-delete after one year.

2. Podcast and music downloads. I found eight episodes of a podcast I finished listening to six months ago. Spotify and Apple Podcasts auto-download new episodes and never delete them unless you tell them to. Go into your podcast app settings and turn off auto-download. Then delete all downloaded episodes. I freed 12 GB this way alone.

3. App cache. Apps like TikTok, Instagram, and YouTube store cached videos and data that accumulates by the gigabyte. On iPhone, the nuclear option is deleting and reinstalling the app (which clears cache). On Android, go to Settings > Apps > [app name] > Storage > Clear Cache. Safari/Chrome cache on either platform can eat 2-3 GB by itself.

The sneaky ones you never check

Recently Deleted folder. When you “delete” a photo, it goes to a Recently Deleted folder for 30 days. Those photos are still taking up space. iPhone: Albums > Recently Deleted > Select > Delete All. Android: Google Photos > Library > Trash > Empty Trash. I had 6 GB of photos I thought I’d deleted months ago.

Offline maps. If you’ve ever downloaded Google Maps or Apple Maps for offline use, those map files are still there. Google Maps > tap your profile picture > Offline maps. Delete maps for places you’re not actively traveling to.

Duplicate photos. Burst mode shots, HDR duplicates, screenshots of things you then immediately forgot about. On iPhone, Photos > Albums > Duplicates (iOS 16+). On Android, Google Photos has a “Free up space” button in settings or use the Files by Google app.

• Messages: Delete large photo/video attachments, set auto-delete to 1 year
• Podcasts/Music: Turn off auto-download, delete old episodes
• App cache: Clear cache in settings or delete/reinstall bloated apps
• Recently Deleted: Empty it — those “deleted” photos still use space for 30 days
• Offline maps: Delete maps for places you’re not visiting