| Technique summary | |
| Technique | Single instance launch |
| Against | Task hijacking |
| Limitations | Only one activity can be a part of the task |
| Side effects | Interaction model can be confusing for the users |
| Recommendations | Not recommended for use by Google in most cases. |
Single instance activities permit no other activities to be a part of its task. If any exported activity in the application is launched in a single instance mode, it is impossible for a task hijacking technique to insert a malicious activity on top.
However, protection comes at the expense of usability. In particular, the order of activities appearing on screen can be confusing for the user.
Because of the significant usability impact, using this technique is not recommended for most cases.