RE: IOTA price $0.60 ----> $0.00000049 in one day !!!!!

This is what @recrypto had to say about it:

For just clarifications for the unit used on IOT.

By default the exchanges uses:
MIOTA != IOTA

So the current price is $0.53 per MIOTA and not $0.53 per IOTA.

1 IOTA = $0.00000053
1 meta-IOTA = $0.53
1 giga-IOTA = $530

1 mega-IOTA = 1,000,000 IOTA
1 giga-IOTA = 1,000,000,000 IOTA

*Spot market price as of 2017-06-15

At first, I got confused as well. XD

The reason behind it though as I've read is to eliminate decimals in transactions.

Hope it helps!