Tap on the line icon next to the MetaTrader logo.

Tap on Manage Accounts.

Tap on the stacked boxes to reveal the menu options for this account.

Choose Change Master Password and enter your present Live MetaTrader account password in the first text box. In the second and third text boxes, enter the new Live MetaTrader account password that would like to use and tap on Next.

A text box confirming your change will appear.