I have got the mudi portable 4G LTE Router GL-E750.
I am very disappointed. I tried three different SIMs.
SIM from Deutsche Telekom: autosetup - did not work at all
SIM from Vodafone - only IPv4 did work (I expected dualstack)
SIM from Telefonica - IPv4 did work (Telefonica only provides CGN IPv4)
I expected a little bit more from a device with the only purpose of routing. A lot of cheaper smartphones provide problemfree hotspots under the same conditions - with IPv6, with dual stack with IPv6-only.
I tried also the latest prerelease /testing version. But it did not change. Where should I start to get it running?