iPhone 4 is an awesome smartphone. It is capable of many things. Unfortunately, it can’t run forever. The last thing you want to deal with is your phone running out of battery when you are on the go. That’s where battery extenders come into play. They add hours of play time to your phone and let you get more out of it when you don’t have access to a power outlet. Here are 5 iPhone 4 battery extenders that offer just that:

New Trent ultra-pack IMP880 8900mAh External Battery pack: works with iPhone 4 and iPad. Adds 50 hours movie time for iPhone 4 and 20 hours movie time for 3G iPad.

Satechi iCel 4800 mAh (2 amp) Battery Extender: a high quality battery extender that works with your iPhone and other USB powered devices.

splash O2 Lite Slim-Profile Extended Rechargeable Battery Case: a hybrid accessory for iPhone that not only adds hours of play time to your iPhone, it protects your device from scratches too.

New Trent Dual-port Pack IMP50D Battery Extender: adds 38 hours movie time to iPhone 4. Allows you to charge 2 devices at the same time.

Konnet PowerEZ Plus Lithium Battery Pack: a portable battery that adds to your battery life. It has a kickstand that keeps your device secure on your table or desk. It offers short-circuit and over-current protection too.

What’s your favorite battery extender for iPhone 4?

Those of you who have owned your iPhone for a while know that a decent case and a battery extender are the two most important accessories you can own for your iPhone. Wouldn’t it be nice if you could get both of them in one shot? That’s what New Trent IMP130 Slim-Fit Battery Case offers. The concept is nothing new. We have seen many battery cases for iPhone in the past. But not too many of them are as slim as this one. Besides, it’s very sleek looking too.

The case is pretty attractive and protects your device against scratches and minor accidents. The battery extender is pretty impressive too, adds up to 8 hours of talk time to your iPhone. Its 1300 mAh battery can be recharged about 500 times. IMP130 is pretty easy to use. All you have to do is slide your iPhone into it. You won’t have to wrestle with this to get it done (unlike some other solutions on the market).

New Trent IMP130 Slim-Fit Battery Case has a warranty of only 6 months. While that may not be too attractive, that is pretty standard when it comes to battery cases. This case protects your device and powers it up. What more can you ask for.

One of the biggest issues with iPhone is the battery life. iPhone 3GS has been improved in this area, but if you own an iPhone 3G, you are probably tired of having to keep charging your iPhone every couple of hours. That’s where battery extenders such asTekkeon MP1200 come in. These solutions not only enhance your iPhone’s battery life, they charge your phone as well. Tekkeon MP1200 myPower iPhone Battery/iPhone Sleeve actually does more than that. It is not only a cool battery extender, but it’s also a decent case that keeps your iPhone safe.

Tekkeon MP1200 comes integrated with a battery that doubles the life of your iPhone’s battery. Once you connect it to your computer, it charges its own battery and your iPhone’s battery at the same time. MP1200 also acts as a dock and syncs your iPhone with iTunes as well. I was very impressed with MP1200 as it really lived up to its promise. The case is solid and protects your gadget against scratches and everyday wear and tear. If you are looking for a case and battery extender at the same time, there is no better way to get them both than picking up Tekkeon MP1200.

Kensington Mini Battery Extender does exactly what it promises to do. It helps you get more out of your iPhone 3G when you are running out of battery. It extends play time up to 30 hours of music or 6 hours of video (on iPod nano 3G) or 3 hours of talk (on iPhone). That means if your iPhone runs out, and you don’t have immediate access to a place where you can charge your phone, you can use your extender to stay in touch.

What I like about this battery extender is the fact that it’s very portable. You are not adding a lot of bulk by adding this add-on. And you can charge your iPhone and Battery extender at the same time. It’s mainly for emergency situations, but it does the job well. If you are looking for an insurance policy just in case your iPhone’s battery runs out, Kensington Mini Battery Extender is a good iPhone accessory to consider.