TUYA equipment works via WiFi and can be controlled / monitored with a mobile app. It often works with Alexa and Google Home too.
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Lot's of choice and generally cheap, especially when ordered directly from China.
Although WiFi is usually a Pro, it can become a con if your house disturbs the WiFi signal or the distances are too great.
Con Motion detection
For camera's the Tuya app only offers simple motion detection and lacks advanced motion detection options like human detection, zones and tripwire.