Sorry for this newbe question, maybe also in some extent OT.
Is it any (free) MQTT client for Android that can interface with flespi MQTT broker?
You can use mqtt-board https://flespi.com/tools/mqtt-board Just open https://mqttboard.flespi.io/ in browser ;)
MQTT TILES on mobile is good , if you are looking for native android app with push notifications etc , look at https://play.google.com/store/apps/details?id=com.kloudip.Hazer&hl=en&gl=US
and MQTT dash app works with Flespi MQTT broker
