The Boostcase Hybrid battery case is composed of 2 parts – a slim fit snap-on case and a detachable extended battery sleeve. I got the white/white combo which consists of a matte white slim fit snap-on case and a glossy white detachable extended battery sleeve. There are other color combinations to choose from like black/black, red/white, and blue/white, among others. You can also get additional slim fit snap-on cases separately so you can use a different colored snap-on case depending on your mood (or your outfit).
The snap-on case is a bit thick – 2mm on the sides and 3mm at the back. The usual snap-on cases are about 1mm thick. With the case attached, my iPhone 4S still feels slim though, and the added thickness provides more bump protection. The rear camera cut-out is sufficiently large and painted black to eliminate any glare when taking photos with the LED flash. The volume and sleep buttons, ring/silent switch, headset port, and 30-pin dock connector port are exposed and easily accessible. You can also use a back protection film with this case with no issues whatsoever.
To attach the extended battery sleeve, you just have to align the pear-shaped cut-out on the rear of the case with the circular locking mechanism of the battery sleeve and slide down. Charging will start automatically. At the bottom of the battery sleeve is a power switch and 4 LEDs that show how much power is left. There is also a micro-USB port that can be used for pass-through syncing and charging. Rated at 1900mAh, the extended battery sleeve provides a charge of about 85% from 0% which does not “double battery life” as indicated on the box – although 85% more power is more than enough. Charging time is +1% per minute.
The Boostcase Hybrid can be had for PHP3,550 (includes a slim fit snap-on case, detachable extended battery and a micro-USB cable). The slim-fit snap on cases can also be bought separately for PHP950 each and comes in a variety of colors – red, blue, black, purple, yellow, gray, pink, peach, and white. The Boostcase Hybrid is available at Digital Walker, Beyond the Box, and Technoholics.
Plus: Detachable extended battery sleeve keeps the iPhone 4/4S slim when extra power isn’t needed; Lots of colors to choose from; Provides 85% power per charge which is quite good; You can use a back protection film with this case
Minus: No lay-on-the-table protection; A bit bulky with the extended battery sleeve attached