Can anyone suggest an OpenWrt compatible device for work in remote areas where reception is poor?
What do you mean with "remote areas"?
If you are talking about outdoor, you can try out the LibreRouter, an Open Hardware and Open Software wireless router for mesh networks.
You can use it to extend the network as much as you want in 2km hops in a mesh topology.
Thanks for the suggestion, never heard of one of these before, although it doesn't seem to be the sort of thing I'm looking for... I need something which takes a SIM card and a WWAN interace - Not sure if this does. The two options I've shortlisted so far is the GL.iNet Spitz and a PC Engines unit. The first one is more affordable but am not sure if I can connect a WWAN antenna to it...
You can add a 3g mPCIe adaptor to it, it already comes with the required sim card tray inside.
Had another look but can't find any pricing or availabilty information...
You can also check for WE-826T from ZBT, on alibaba, for example. Rather cheap, and reliable. Replace the standard antennas with something special, if you need.
Using a QUECTEL EC25 is a good combi.
Just came across a MikroTik RouterBOARD M33G - https://mikrotik.com/product/rbm33g and wondered if anyone has any experience with one of these...
You can send an email to email@example.com for pricing and availability.
The router is U$S 165 + shipping and customs.