回答“How to test if the Tristar has failed or the battery”Interesting info! You can also use an ammeter or something like the Kaisi battery activator ($20 unit with some other benefits for repair techs) to determine if the Amp draw through the lightning port is within normal range. I'm a bit hesitant personally of unplugging the battery while sending a charge through the lightning port. It maybe safe, but it seems like there is potential to cause issues due to how touchy the Tristar is to voltage irregularities in the first place.
回答“Want to buy correct battery”I have replaced the 0432 with the 0435 without issues many, many times in the past. I always try to keep the 616-0435 in stock in my store because it seems to be the most universally compatible APN. I also will add that sometimes replacement batteries from some vendors are just plain faulty. Nothing is more frustrating than getting a replacement battery that has issues just due to poor manufacturing or not being properly tested. Look for "genuine" or "original" specification if you can find them. It will limit your chances for getting a junk part. You get what you pay for!
回答“Back cover for the iPhone 4s the same as iPhone4?”The CDMA iPhone 4 back panel is compatible with the i4s. GSM i4 back panel is NOT compatible with iPhone 4s. So basically a Verizon or Sprint iPhone 4 back will fit any iPhone 4s and vice versa. Hope this helps, Chad