ClearFax sends faxes from your iPhone, iPad or Android phone, without a fax machine. Scan the paperwork with the camera or pick a PDF, enter the fax number, and send. You pay per fax. One purchase covers one fax of up to 50 pages, and you see the price before you pay. There's no subscription and no account. Each fax that goes through gets a receipt PDF with the destination, page count, time and result. If the fax network reports a failed send, your purchase isn't used up and you can resend the same pages at no extra charge. Some number ranges are not supported. ClearFax only sends faxes; it can't receive them.
ClearFax is for people who rarely fax and need to send one, such as an IRS, Social Security or insurance form. Most fax apps are sold as subscriptions, so ClearFax charges for one fax at a time instead.