BTW , umidigi f2 was officially announced, USD$250 releasing on 10/14
https://www.umidigi.com/page-umidigi...ification.html
Page says this, not sure if it's implying dual SIM dual active LTE/voice? Haven't kept up with how dual sim works with LTE, is it possible for a dual standby device to keep both LTE sessions open?
Dual SIM use:
Both SIM slots are compatible with 4G, support 4G VoLTE in both slots simultaneously.
Also, dual SIM and microSD can all be used simultaneously, most of their recent phones share sim2 slot with microsd
My s3 pro should be coming tomorrow