The costs for switching isn't that high. Most people don't spend a lot of money on apps. More than half of the money is spent on games anyway. These are played for a while and then new games are purchased.

The handful of productivity apps won't exceed 20$ for the vast majority of users.

I buy lots of apps and games. Every time I switched platforms (webOS -> Android -> iPhone -> WP), I spent around 15$ to cover my initial needs. Compared to what I pay for a phone, it's negligible.