It depends what the expenses were used for.
If you are required by your employer to have a cell phone and to use it for the convenience of your employer and your own - you may deduct the business use portion of the phone as job related expenses. Otherwise, the expenses are considered personal and are not tax deductible. Job-related expenses are located in:
Federal Taxes
Deductions & Credits (you may have to select See all tax breaks)
Employment Expenses
Job-Expenses for W2 Income
If you are self-employed and use your cell phone for "your business", you can deduct them as your business expenses.
Federal Taxes
Wages and Income
Self-Employment, Select Income and Expenses - follow the interview questions; you would report the income as if you own a business; and then your cell phone expenses. Note: you may be asked to upgrade to a higher version of TurboTax.