 AUSTIN, Texas, June 15, 2021 PRNewswire -- Sonim Technologies Nasdaq: SONM today announced that its XP8 ultra-rugged Android handset is approved for FirstNet Push-to-Talk PTT, the nationwide mission-critical standards-based push-to-talk solution. FirstNet is built with ATT in a public-private partnership with the First Responder Network Authority FirstNet Authority an independent agency within the federal government. 