I made a form in acrobat and put formula in some fields, it works perfectly. But I sent it to someone else and they can't fill it out, and the formula field doesn't work. So I tried opening it on my cell phone to see if i can fill it out and its ok but the formula doesn't work either! Can you help me to make the form work on other computers and cell phones?
You can't. Unfortunately the mobile versions of the PDF viewers that are available all are different from the desktop version of Adobe Acrobat or the free Adobe Reader as far as support for interative forms and scripting goes. And when I say "different", I mean, they are lagging in features. Even Adobe's own viewer falls into this category. There are some PDF viewers that have more support for those features, but they are not free, and you would still have to design your form specifically for one of these applications.
The only way you can get the same behavior on desktop and mobile devices is by leaving PDF behind and moving to web technology.