Yes, can confirm both (1) Flying is also possible without WiFi (smartphone or tablet). (2) And: NOT RECOMMENDED. It is almost impossible to keep the thing stable in the air. No GPS, no stabilisation, the camera (of course) has no gimbal. You can get something decent for less than 200 more, e.g. the DJI Spark.

No, it doesn't need a Wi-Fi connection. And the question of battery life is superfluous because you can hardly get the thing to fly properly. As others have already said: Keep your hands off it!