Which is the best smartphone brand for work and business?

From my point of view, the best smartphone that can be used for private usage as well as for work is the smartphone that has these features at least:

1. It is possible to be accomodated in your pocket, so you can move with it easily.
2. It supports the main applications needed like office app.s and others.
3. It has enough resources to accomodate your data.

That said, I don't care it was from Apple or from Samsung or from any other brand name.