Hello dear, 

You can use the following tips, in order to avoid your cellphone while studying: 

• Put your cell phone on silent mode and place it in other room. 
• Keep your internet access off. 
• When you take break from studies, go for a walk or take fresh air, use your cell phones to a minimum. 
• Use air plane mode. 
• Put your phone on do not disturb mode
• Inform your friends that you wont be available for some hours.
• Give your phone to someone else like your family members, if you cant stay away from it. 

I hope all this will help you. 

All the best!