When I start my Drone in gps mode, every thing is fine. When the drone is started, I swiched the mode to atti, and it trys to take off. Please help!!

You mean when the AC is started?  Or do you mean when the motors are started...?

Hi Jonah, sorry for the trouble. May I know if you are receiving an error message? If yes, please provide a screenshot for further check. May I know if you are flying indoor? Kindly choose to fly your drone in an open wide area with no interference and please let me know if the issue persists. Thanks for your support.

You need to practice atti mode in a very open area.  When you open atti, you have no gps assistance.

When the motors are started, in GPS mode everything operates properly. When I switch to Atti mode, the props start acclerating. My Dad is holding the drone down to the floor inside, but if he wasn't, it would be gone! I am hesitnt to try it outside because I don't want it to take off and hit something. Also, I just got a Samsung Tab A Tablet to use with the drone. Could it have anything to do with that? Is there a way to reset the whole drone to default factory setting and re install firmware? I did a IMU calibration and it still behaved the same. I tried using my phone and it still didnt work. When I lay my phone on the ground the gps signal gets weak and the drone motors seem to function normal in any mode when I pick my phone up off the ground the gps signal increases to 5 bars and the motors stsart to act up?

As DJI Paladin says, don't fly your drone inside, especially in ATTI mode.  Go outside in open area to fly.  You will crash flying inside far faster than outside.  Take off in P-GPS, take it up and out 10M or so, then switch to ATTI.  It flies differently in ATTI than GPS mode.

Jonah Posted at 1-26 11:17
When the motors are started, in GPS mode everything operates properly. When I switch to Atti mode, the props start acclerating. My Dad is holding the drone down to the floor inside, but if he wasn't, it would be gone! I am hesitnt to try it outside because I don't want it to take off and hit something. Also, I just got a Samsung Tab A Tablet to use with the drone. Could it have anything to do with that? Is there a way to reset the whole drone to default factory setting and re install firmware? I did a IMU calibration and it still behaved the same. I tried using my phone and it still didnt work. When I lay my phone on the ground the gps signal gets weak and the drone motors seem to function normal in any mode when I pick my phone up off the ground the gps signal increases to 5 bars and the motors stsart to act up?

The ATTI mode is a manual mode of flying the aircraft. In GPS mode, the aircraft is kept stable in the one place by the GPS signal received. But in ATTI mode, nothing is keeping the aircraft stable, it is able to be blown around by the wind.
The simple answer to your problem is not to put the aircraft in ATTI mode until such time as you are able to manually control it properly.

I know the rotors of the AC spin  faster in start of the ATTI mode. But i newer had the issue that the AC begins to take of without my commands. ATTI is for indoor too but you need a wide area for it.
The best is you practice the ATTI on an open field first so you are sure your bird can be controlled freely without any obstacle. I train to fly in ATTI with a LS128 or Xin Lin X6. The X6 has the same weight as the Phantom 3S and has no helpers like a Phantom .  Try to learn fly in ATTI in steps. ...and always fly safe.

I think if you want to fly in ATTI mode, it's usually best to launch in GPS mode, then switch to ATTI mode once in the air.

OTOH, if you don't have satellites and you are forced to launch in ATTI mode, you shouldn't have a problem in relatively calm winds.  

Good luck

I took my drone outside launched it in GPS then once the drone was in the air I swichted it to atti mode and every thing went perfect thanks for all your help.

Jonah Posted at 1-28 10:20
I took my drone outside launched it in GPS then once the drone was in the air I swichted it to atti mode and every thing went perfect thanks for all your help.

Trying to fly inside is not in your best interest. Especially inside your house. Attempting to hold it down in ATTI mode also doesn't help. I see you took it outside and had good results. As suggested, get in an open area and start off In GPS, then switch to ATTI. Be aware if there are strong winds the aircraft will not hold position. You must be prepared to control your flight, or else switch back to GPS, and the aircraft should regain steady position if satellites are available.

Jonah Posted at 1-28 10:20
I took my drone outside launched it in GPS then once the drone was in the air I swichted it to atti mode and every thing went perfect thanks for all your help.

That's how to do it.  Glad everything worked well.

I have another question awhile back i was flying my drone and while I was in the air I switched to function mode and put it follow me mode as soon as I put it in that mode it took off into a tree haven't tried that mode since if anybody has any tips i would be glad to hear them.

Jonah Posted at 1-28 17:36
I have another question awhile back i was flying my drone and while I was in the air I switched to function mode and put it follow me mode as soon as I put it in that mode it took off into a tree haven't tried that mode since if anybody has any tips i would be glad to hear them.

Classic error.  Sorry.  Before you do follow me mode you must be sure you have a good GPS fix of your mobile device.  They tend to jump around a little, so be sure you are in a wide open area with lots of sky - and then it would hurt to check your mobile device for the little blue dot - making sure it's accurate and stable - before doing follow me mode.  Otherwise you drone might take off into a tree.  

Good luck.  

where would i find the blue dot

I think any time you're using GPS on your mobile device and you have a map on the screen, you'd see a blue dot giving your current location?  That would be the location of your mobile device.  It may or may not be accurate.  Normally you'd want to walk around a little and give your mobile device a chance to acquire satellites and fine tune the fix to improve the fix.  And it helps a lot to be under open sky.  

I'm referring to android here.   Various apple devices are different I think.  

The point of all this is... the drone does not follow YOU.  It follows what it believes is the location of your mobile device.  So you want to be extra double sure it's an accurate location and not set at a spot located a half block away.  Because if it is, your drone will fly away for a spot located a half block away.

It would be beneficial to learn how to cancel the follow me function quickly to avert a crash due to your drone suddenly flying a half block away.

Good luck.  

i didn't have enough room from the drone and the tree so didn't have time to cancel  witch means I should probably use that mode in a open area like you have mentioned also I am using a android device for my drone

another question when i was flying my drone i tested the max range on the the drone and my video feed was very laggy and skippy i lost connection and said it was returning home but it didn't so i did a return home by pressing the return to home button and it said return to home was canceled and it was very hard to take back control and land it safely if anybody knows why this happened that would be very much appreciated.

Jonah Posted at 1-29 20:44
another question when i was flying my drone i tested the max range on the the drone and my video feed was very laggy and skippy i lost connection and said it was returning home but it didn't so i did a return home by pressing the return to home button and it said return to home was canceled and it was very hard to take back control and land it safely if anybody knows why this happened that would be very much appreciated.

If it is returning home and you press the RTH button, it will cancel RTH. That is perfectly normal. Just press it again. The action alternates betweeen returning home and cancelling the function every time you press the button.

I pressed the return to home  button because it wasn't returning  home

Jonah Posted at 1-30 21:06
I pressed the return to home  button because it wasn't returning  home

What do you mean when you say "I pressed the return to home button"?  Please be specific.