Every protocol you save — from any InjectBuddy calculator or added here — has a start date and an injection frequency (for example every 3.5 days, or once weekly). The calendar projects those forward across a rolling multi-month view and marks every due date, so you can see your whole schedule at a glance. Tap any day to scroll down to its protocol cards: the dose, the draw volume, and a suggested injection site that rotates automatically so you don't hit the same spot twice in a row. It only lays out the days your protocol already implies — it never changes a dose or volume. How often you inject is driven by the medication's pharmacology (depot ester half-life for testosterone; the once-weekly profile of GLP-1 agonists). The site rotation is a generic aid only — always confirm timing and injection site with your prescriber.