Currently, 4G smartphones on the market allow only the primary SIM card to support VoLTE, while the secondary card can only use 2G/3G, which diminishes the calling and internet browsing experience.
And In some regions 2G/3G spectrum is being “re-farmed” and some operators are exclusively 4G-LTE only.
Now we provide three smartphones UMIDIGI A1 Pro, UMIDIGI Z2 and UMIDIGI Z2 Pro, which support Dual SIM Dual VoLTE. In other words, In these smartphones both SIM slots are compatible with 4G, support 4G VoLTE in both slots simultaneously.
UMIDIGI A1 Pro silver limited edition presale starts on 28th May from $99.99 at Gearbest http://bit.ly/umidigia1pro
UMIDIGI Z2 opens presale subscription at http://bit.ly/umidigiz2pro. Presale will start from $249.99 on 11th, June 2018, 8:00 AM(UTC)
Source: Umi Mobile Youtube
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