... Voice prompts, easy to operate, can be installed GSM phone cards,two-way intercom function. 2. The ... control. 4. Phone, APP or SMS remote host system settings.(ios app, just search "gsm alarm" on ... remote monitoring, propaganda function, and can remote phone or send text messages to the host arm, ... using dual band, tri-band, quad-band frequencies GSM / GPRS industrial module, stable and reliable. 11. ...