While each mode is unique and important to understand, most of them still provide the basic function of flight-stabilization and assistance tool. For instance, OPTI typically features an Optiflow sensor within the drone, which is a downward facing sensor capable of identifying patterns on the ground and helping the machine to maintain a straight position.
On the other hand, ATTI is a partially different tool, whereby the quadcopter uses other techniques and not necessarily external sensors to firmly hold the drone in correct altitude and orientation. ATTI allows the drone to hover in place, as well as to gently drift around while being pushed by the wind. Some drones also have GPS which offers great precision and coordination during flight.

Please note that if these drones are flown out of range so that the communication with the drone is lost, the drone can be easily lost as well. A common error is to fly the drone to its height limit and lose communication. If there is any wind, the drone may then do what is called a “fly away.” This is a sad thing for an operator because the drone will fly off to who-knows-where and unless you quickly go chase it; it can disappear forever. 

The Altair AA108 is durably built and will not break easily. You can count on a solid flight time of around 10 minutes, a bit less when you’re running it FPV. However the 720p camera really works well and connects to your phone through WiFi. It’s easy to fly because it has 3 flight modes, 1 beginner, 2 intermediate and 3 advanced mode. It also has Altitude Hold which allows you to take your thumb off the control and the drone holds it’s own altitude, making it very stable because it’s not bouncing up and down as you try to maintain altitude!
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