I imagine I would pick the phone over the toilet. Seems like an easy choice.
The phone offers to be a multiplier for my life. Whatever I'm doing, the phone may be able to help me do it better. I can get in touch with experts, find guides and advice, make better plans, etc.
Programmers often talk about how indispensable Stack Overflow has become for programming. Regardless of how necessary it is, it certainly can make you more efficient. The same principle can apply to almost anything.
Looked at it from that perspective, it reminds me of Homer Simpson finding a $20 bill and thinking, "Aww, I wanted a peanut!" His brain replies, "$20 can buy many peanuts!" I think that having a phone could eventually let me buy a toilet, but having a toilet doesn't particularly help me buy a phone.
Of course, I say all of this from my first-world house where both the phones and the toilets outnumber the inhabitants by roughly 2:1, so I could be way off.