It’s for my (very) old phone to feed my eldest’s Pokémon addiction (and help get him out of the house and get some fresh air). Something where the data lasts a long time (or credit doesn’t expire). A bit of Googling suggests the app uses between 8-20mb/hour. I can’t imagine more than 3-4 hours use per week, less as we get into Autumn. It’s currently got a 2GB EE data SIM in it that I got free, but it only lasts 30 days and will expire shortly.

I thought about the Three data SIMS, but the 12GB that lasts 12 months is massively overkill based on the above. The phone is unlocked. What SIM do people use in trackers/security systems etc. as I assume their requirements are similar? Thanks.