do i get a better new battery for go for a Back-Up Battery Charger
Back up battery charger. The cheap "higher capacity" batteries are no better (sometimes worse) than the standard one that comes with the phone.
soo i go for a Back up battery charger for my htc desire hd
What you do with the battery also makes a difference. Like El Presidente said, even 'extended' batteries are usually a bit of a let down compared to the stock one, so they don't usually make great replacements. But if you're intending to carry both batteries round, then it can't hurt. They are small enough that you can stick one in your wallet without much of a noticable bulge.
I don't know how the backup battery chargers compare in terms of the extra power you get, but it's certainly less hassle to switch to a new battery than it is to charge the stock one whilst out during the day.
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