A system function invoking method performed by a terminal comprising a system, and a first application program and a second application program both being installed on the system, wherein the method comprises: • configuring, by the system, at least one first mode in the system and configuring, by the system, at least one system function for each of the at least one first mode and presenting, by the system, the at least one first mode to a user of the terminal, wherein each of the at least one first mode is used to, when the system is in the first mode, forbid, by the system, a second application program from invoking at least one system function defined in the first mode (step 701); • receiving, by the system, a selection of the first mode among the at least one first mode from the user, wherein the selected first mode is a mode in which the system is in when a first application program is in a running state (step 702); • configuring, by the system, the system, so that when the first application program is in the running state, the system is in the first mode (step 703); • starting the first application program, and receiving, by the system, a message from the first application program that the first application program is started, so that the system determines that the first application program is in the running state (steps 704, 705); • enabling, by the system, according to a record in the system, the system be in the selected first mode (step 706); • notifying, by the system, the first application program that the system has disabled a first Application Programming Interface, first API, corresponding to the at least one system function of the selected first mode (step 707); • running the first application program (step 708); • invoking, by the second application program, a second API for which a permission check is required (step 709); • searching, by the system, for disabling information of the invoked second API (step 710); • if the system finds the disabling information, returning, by the system, a null value or a false value to the second application program (step 711); • exiting, by the first application program, the running of the first application program (step 712); • notifying, by the first application program, the system that the first application program exits running (step 713); • exiting, by the system, the first mode, and allowing, by the system, the second application program to invoke the at least one system function of the selected first mode (step 714). • configuring, by the system, at least one first mode in the system and configuring, by the system, at least one system function for each of the at least one first mode and presenting, by the system, the at least one first mode to a user of the terminal, wherein each of the at least one first mode is used to, when the system is in the first mode, forbid, by the system, a second application program from invoking at least one system function defined in the first mode (step 701); • receiving, by the system, a selection of the first mode among the at least one first mode from the user, wherein the selected first mode is a mode in which the system is in when a first application program is in a running state (step 702); • configuring, by the system, the system, so that when the first application program is in the running state, the system is in the first mode (step 703); • starting the first application program, and receiving, by the system, a message from the first application program that the first application program is started, so that the system determines that the first application program is in the running state (steps 704, 705); • enabling, by the system, according to a record in the system, the system be in the selected first mode (step 706); • notifying, by the system, the first application program that the system has disabled a first Application Programming Interface, first API, corresponding to the at least one system function of the selected first mode (step 707); • running the first application program (step 708); • invoking, by the second application program, a second API for which a permission check is required (step 709); • searching, by the system, for disabling information of the invoked second API (step 710); • if the system finds the disabling information, returning, by the system, a null value or a false value to the second application program (step 711); • exiting, by the first application program, the running of the first application program (step 712); • notifying, by the first application program, the system that the first application program exits running (step 713); • exiting, by the system, the first mode, and allowing, by the system, the second application program to invoke the at least one system function of the selected first mode (step 714).