We didn’t force it. Bought the potty and “big boy” underwear. He was excited to try them at first but ultimately wanted to go back to diapers. We kept the potty out and continued to ask him if he wanted to try underwear. Eventually (several months later) he warmed up to the potty and the switch to underwear soon followed. This happened maybe a couple months after his peers—but we never had a single accident and we didn’t have to do any traumatic training. It was a very smooth transition.
You can already get big phones though.