Its not an Eye-fi card but an SD wifi adapter with a micro sd class10 inside. Its the same. My android or iphone cant find the wifi card. But if i play a video with the 5100 (the green light of the card reader on) i can find the the card. In conclusion, i need to put energy on card to find im. I try on a Pentax compact camera and with the power on, the card its always available.