If cell phones are no longer listed property, then you can deduct the percentage of your repairs that is the same as the percentage of business use, and you can depreciate the percentage of the cost that is the same as the percentage of business use without worrying about the 50% limit. You are still supposed to have a record that allows you to determine the percent of business or personal use. If you don't have records proving the percentage of business use, then, if you are audited, the result would depend on whether your particular auditor thinks your estimate is reasonable. Auditors do not have to give you a deduction you can't prove, so it's up to you how much risk you want to take.
