Things to consider when trying to wean children off TV or technology:
Children are people, not objects. So, don’t impose new changes on them. Have a conversation and negotiate where necessary.
Be involved. Make time to play with your children outside of the magical screen world. If you’re not available, hire someone or call on a friend to take on this role.
Introduce and buy your child toys. Especially puzzles and dolls as these will encourage imagination and creativity, taking them away from the passive isolated play that comes with gadgets.