I'm currently self-employed doing computer programming work. As part of self-employment I'm learning about filing taxes quarterly (not fun) and also writing things off as business expenses (potentially more fun).
Say I purchase a new iPad for the sole purpose of testing and developing apps for clients. I don't use this iPad for watching movies or reading non tech industry and development related news. So it's just for business purposes.
What are the ins/outs/gotchas of writing this purchase off as a business expense?
I've been saving my receipts but that's about all the preparation I'm doing. I'm wondering if there's a minimum amount of income one needs to earn in a year to qualify for writing off things as business expenses.