Apps like Cellular Connection Monitor

Here are some great alternatives to Cellular Connection Monitor by Pavel Borzenkov :
Cellular Data Notifier
Cellular Data Notifier
★4.7
GSM Signal Monitor & SIM Info
GSM Signal Monitor & SIM Info
★4.4
Signal Monitor
Signal Monitor
★4.3
Cell Signal Monitor
Cell Signal Monitor
★4.2
NetMonitor Pro
NetMonitor Pro
★4.7
Signal Strength
Signal Strength
★4.3
4G LTE / 5G coverage monitor
4G LTE / 5G coverage monitor
★4.2
NetMonitor Cell Signal Logging
NetMonitor Cell Signal Logging
★3.8
Smart Notify - Dialer & SMS
Smart Notify - Dialer & SMS
★4.0
Cell Signal Monitor Pro
Cell Signal Monitor Pro
★4.2
Jammer Detector
Jammer Detector
★4.0
Site Monitor
Site Monitor
★3.6
Flash Alert - Call & SMS
Flash Alert - Call & SMS
★4.8
notistory - All notifications
notistory - All notifications
★4.1
Signal Info
Signal Info
★4.3
Missed Phone Call Notification
Missed Phone Call Notification
★3.9