The best replacement for alarms is viper.

The best alternatives to alarms are rated as following:
★★★★★  viper
★★★★  police patrols
★★★★  viper alarms
★★★  smoke detectors
★  clifford alarms
★  bells
★  warnings
★  ionization
★  hardwired
★  wired alarms
  alerts
  wired
  fire alarms

Your alternative for alarms is not listed? Suggest!
Speaking about alarms, one probably shouldn't forget about proximity sensors.

Other search terms related to alarms and their ratings are:
★★★★★ proximity sensors
★★★★★ motion sensors
★★★ sensors
You have in mind a companion for alarms and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of alarms in all years. Click on graph for more.
alarms
viper
police patrols