The iOS signature itself is done online, and some have never even made a voice call, so it is easy to be cheated. In the past two years, with more and more signers, the signature market is really getting more and more chaotic, swindlers are more rampant, and there is no standard to measure prices, so many people simply can't tell the truth from the false. The loss in the early stage of discovery can be smaller, and the loss in the later stage of discovery can be tens of thousands of dollars. Therefore, everyone must find a formal and reliable platform for cooperation.