Logsave.me is an app designed by legal and tax professionals that solves two problems: First.- the counting of days for tax residency purposes, in a country or region. Second, it avoids identity theft in digital signatures. It applies technologies such as facial biometrics, encryption, time stamping, GPS and blockchain, and it has worldwide scope of application. The App generates irrefutable and unalterable evidences that can additionally be processed by the user's trusted professional. The main purpose applied in the whole process chain has been to maintain the privacy of the user, who is the only one who has access to the data, using public and private keys.