You can add a yellow calendar to an Iphone calendar.

Calendar software that can be used on iPhone can rely on its own reminder function. If the functional requirements are complicated, you can also install the third-party calendar software.

If you want to set an alarm clock to remind you on Saturday of the second week of every month, you can try to use a special sign.

As a reminder, note and memo software, the dedication sign can be reminded by day/week/month/quarter/year in the date setting;

Support to remind by solar calendar date and install lunar calendar date, and set the interval period, such as interval 1 day, 2-day reminder ... 1 month, 2 months. ...