My 3 year old daughter is addicted to watching cartoons/ toddler programs on YouTube. She's gained the intelligence to even unlock my phone and remembers my passcode very well. How do I get her to lose interest? I usually give in to her during meal times as I want her to finish the food.
They're smart, unlocking the phone isn't a big deal. Try to show her, avoid using it in front of her especially during meal time and give her other distractions.