Quantum key distribution (QKD) and Quantum Secret-Sharing (QSS) are some solutions for secure cryptography against the threats to classical cryptography emerging from quantum computers. Point-to-point QKD schemes are vulnerable to detector side-channel attacks. Measurement Device Independent (MDI) QKD has been presented as a solution to these attacks. Recently an MDI QKD scheme based on differential phase encoding was presented. We analyzed the effect of polarization mismatch on the secure key rates of this protocol and found the permissible level of mismatch of polarization to produce secure keys. We propose a QSS scheme based on time-bin superposed states with differential phase encoding. The scheme is analyzed under arbitrary collective attack, and an achievable secure key rate is derived.