My iPhone 4S is constantly running low on battery, especially when I’m travelling (or when I spend all day in the cigar lounge), so I’ve been on the lookout for a portable battery pack – especially since my mate Grant was here from NZ a month ago and showed me his (battery pack, that is… get your mind out of the gutter).

Then I got an email from the folks at Sandberg promoting their “PowerBackup for iPod + iPhone” 420-05 unit. They were nice enough to send me a review unit and I’ve had a few days to test it.

Out of the box it had a 75% charge on the unit but I wanted to test  it fully charged, so I plugged it into my iPhone charger for a while.  According to the Sandberg site, charging time takes 2-3 hours by AC adapter or 4-5 hours by PC. Mine fully charged on the AC adapter in about two hours.

Then I let my iPhone 4S run down to 0% and jacked the Sandberg in. After two hours, the Sandberg unit was depleted and the  iPhone was sitting at 76% charged.

While it was charging, the iPhone was powered up (in sleep mode for most of the time), NOT in airport mode and with WIFI turned ON. I figured it might charge faster with everything turned off, but if I’m using this in a real-life situation, I typically want my phone on while it’s charging.

The Sandberg has four capacity LEDs, letting you know how much charge is in it, and another LED to let you know when they iPhone is charged. It also holds its charge very well. I recharged it after the experiment, and several days later it still has a full charge.

I also tried the Sandberg on my iPad 2 but it wouldn’t charge. It’s not advertised as compatible for iPad so I wasn’t surprised, but I just wanted to test it anyway.

Unfortunately, I haven’t been able to find them for sale in Australia yet. According to the Sandberg site, the RRP on these units is  £21.99 (about $33 AUD) but you can find them on for less.

Definitely gets a big thumbs up from me.