I can read amazon too.
Link for the lazy: http://smile.amazon.com/dp/B00SDY3RLO
I got one of these https://www.amazon.com/dp/B00SDY3RLO/ref=cm_sw_r_other_awd_AO26wbBWPT40Vfor Ingress and Geocaching. Charges my G4 from 15% 3 or 4 times.
Screw Anker, I went with this and I love it.
also comes with an ingress code to redeem a few viruses and power cubes.