I'm currently designing another project using an esp that must connect to WiFi and upload data periodically.
The problem is: It will not always have access to the local WiFi network.
My workaround: have the device set up its own network by connecting it to a SIM card or by using a Surfstick.
The problem: Size of the device is a concern. I can't use anything larger than a dozen mm in depth. (length and width matter a bit less.) So large boards like GSM are mostly off the table.
I am wondering if a surfstick such as this would be sufficient, and perhaps acceptable in size and durability:
This brings up a new problem - I have no idea how this should be connected to an esp. Can it even be done?
Thanks for the advice!