You said "Some devices, such as the newer iPhones and the MacBook Air require special screwdrivers to open. Many device use standard Trox and Phillips screws, but there just really small. I recommend"
Perhaps you meant " ...but they are just really small"
they are is abbreviated to they're.
See
http://wiki.answers.com/Q/What_is_the_abbreviation_for_they_areYes I do know that I have "issues" with poor grammar.