To put it bluntly, a single Pi coin is currently worth nothing. Zero.
As a pre-market coin, Pi is trying to gain the following and put the network in place to be effective when it launches, which means that you cannot exchange Pi for actual money right now, nor can you exchange it for a service or good.
But the creators of Pi point out that Bitcoin had no value when it was in its infancy, either.
There are very few people who would not want to get in on the ground floor of Bitcoin back when it first launched, if they could, but it wouldn’t be logical to think that Pi—or any coin—will ever get to the astronomical value that BTC has now.
Because Pi is pre-market, it has drawn some criticism online. Re-enabling your mining every day prompts a video ad that the app creators profit from, which means that it is income-generating for those who have a stake in the app itself.
Also, the idea of you benefiting from recruiting more people into the network leaves a sour taste in the mouths of some, with a feeling similar to a pyramid or multi-level marketing scheme.
That being said, proponents of Pi are quick to point out that there is no investment needed in the crypto coin right now, which clearly differentiates it from pyramid schemes and MLMs.
In its current form, Pi only requires a moment of time invested each day.