Shotsy does one thing well. Most protocols eventually need more than one. Here's what happens when your health journey outgrows a single-shot tracker — and what to use instead.
Starting a GLP-1 medication is a meaningful decision. Whether you're on semaglutide, tirzepatide, or another GLP-1 receptor agonist, you've made a real commitment to your health — and wanting a way to track that commitment makes perfect sense. Apps like Shotsy exist because that instinct is right.
For users in the early stages of a GLP-1 protocol — one injection, one compound, one standard commercial pen — Shotsy works. It's clean, it's focused, and it gets out of your way. But as health journeys evolve, the assumptions baked into Shotsy's design start to show. This article looks at where Shotsy earns its reputation, where it runs out of room, and how Halflife — Peptide & GLP-1 Log was built for what comes next.
Being honest about a competitor matters. Shotsy was designed with a specific, well-defined use case in mind: someone who takes a once-weekly GLP-1 injection from a commercial pen (Ozempic, Wegovy, Mounjaro, Zepbound) and wants a simple way to stay on top of it.
Within that scope, Shotsy delivers:
For someone who picked up a Wegovy pen last month and wants to stay organized, this is genuinely useful. The problem isn't that Shotsy does its job badly. The problem is that health journeys rarely stay this simple — and Shotsy wasn't designed to grow with you when they don't.
GLP-1 medications have become a gateway into a broader conversation about health optimization. Many people who start on semaglutide or tirzepatide find themselves, a few months in, working with a prescriber who adds something else to the mix. Or they're sourcing a compounded formulation on a different schedule than the commercial pen. Or they've started addressing the side effects of GLP-1 dose escalation with a supporting compound.
That's when Shotsy stops being enough. Here's where the gaps appear:
Compounding pharmacies frequently prescribe semaglutide or tirzepatide on intervals that don't match the standard commercial pen — every five days, twice a week, or on a month-long titration ramp that increases the dose at each injection. Shotsy's framework was built for a fixed weekly schedule. It doesn't flex well to accommodate custom intervals, and it gives you no way to visualize how a non-standard schedule affects your compound levels over time.
A significant number of GLP-1 users eventually add supporting compounds. BPC-157 for the gut discomfort that can accompany GLP-1 dose escalation. Ipamorelin or sermorelin to preserve lean mass and improve sleep quality during a caloric deficit. Testosterone or a hormone therapy protocol running alongside the metabolic work. Shotsy has no mechanism for tracking a second active compound — let alone showing you how multiple compounds interact in your system over time. You'd need a separate app for each one, and even then, there's no combined view.
A dose log records what you injected and when. That's useful history. But it doesn't tell you what's happening in your body right now — how much of your GLP-1 is still active at day four of seven, whether your levels are peaking or troughing, or when you'll approach the bottom of your dosing interval. Without that picture, you're making protocol decisions without the information that should inform them.
This distinction is worth understanding, because it's the central reason people move from Shotsy to a more capable GLP-1 tracker app. It comes down to what GLP-1 medications actually do in your body between injections.
Semaglutide, for example, has a half-life of approximately seven days. That means after your weekly injection, the compound doesn't simply sit at a stable level until the next shot — it decays gradually across the week. By day four or five, your levels have dropped meaningfully from the post-injection peak. By day six or seven, you may be approaching your lowest point of the cycle, which is often when side effects ease and appetite begins to return. To understand exactly how that decay curve works week-by-week, see our guide on calculating peptide steady state.
Published pharmacokinetic data on GLP-1 receptor agonists — including dose-proportional exposure and steady-state accumulation behavior — is well-documented in the clinical literature. NIH / StatPearls: GLP-1 Receptor Agonists provides a solid reference for understanding how these compounds behave across a dosing interval.
Now add a second compound with a different half-life. Ipamorelin, for instance, clears your system in roughly two hours — it peaks and troughs multiple times in a single day. BPC-157 behaves differently still. Each compound follows its own curve. Without a visual dashboard that tracks all of them simultaneously, you have no way to see what's active in your body at any given moment. Halflife's compound database covers 45+ peptides and GLP-1 agonists with citation-backed half-life parameters, so every curve you see in the app reflects real pharmacokinetic data.
That's not a minor feature gap. It's a fundamentally different level of information.
Halflife — Peptide & GLP-1 Log was built for users who want the full picture. Not just a record of what they injected, but a clear, visual, real-time view of what their body is actually dealing with. Here's what that looks like in practice:
Add every compound you're taking — your weekly GLP-1, your daily peptides, your hormone protocol — and track all of them together in a single app. Each compound gets its own active level curve, and they all combine into one unified view of what's in your system.
Instead of a list of injection timestamps, Halflife shows you a live visual dashboard of your body's current active levels across every compound you're tracking. You can see where your semaglutide is in its weekly cycle, whether your peptide is near peak or approaching trough, and how everything plots on the same timeline.
Whether you're on a standard commercial pen or a compounded formulation dosed every five days, Halflife handles it. Set any dosing frequency — daily, every 4 days, twice weekly, custom titration ramp — and the dashboard recalculates to match your actual protocol, not a template.
When your active levels are approaching a meaningful low point, Halflife alerts you — before you feel the drop. That information helps you time your next dose with confidence, understand why your energy or appetite might shift at a predictable point in your cycle, and avoid surprises at the bottom of your dosing interval.
The result is a Mounjaro tracking app — or a semaglutide dose tracker app — that doesn't stop at the injection timestamp. It follows the compound across its full arc in your body, alongside everything else you're taking, on whatever schedule you're actually using.
For users deciding between these two tools, here's an honest side-by-side based on what each app is built to do.
| Feature | Halflife — Peptide & GLP-1 Log | Shotsy |
|---|---|---|
| Best For | Anyone managing GLP-1s, peptides, hormones, or multiple compounds who wants a real-time view of their full active levels | Users on a single commercial GLP-1 pen with a fixed weekly schedule who want a clean injection diary |
| Multi-Compound Stacking | ✓ Yes — track unlimited compounds simultaneously with a combined active level view across all of them | ✗ No — designed for a single compound; no stacking or combined dashboard |
| Visual Level Tracking | ✓ Yes — real-time decay curves and a live active level dashboard for each compound in your protocol | ✗ No — injection log and weight diary only; no visualization of compound levels between doses |
| Custom Schedules | ✓ Yes — any dosing interval supported: daily, every 5 days, bi-weekly, monthly titration ramps, fully custom | Partial — optimized for standard weekly commercial pen schedules; limited flexibility for compounded or custom intervals |
Abstract comparisons can only do so much. Here's a concrete scenario that shows what the difference looks like for a real user.
Scenario
For a deeper look at how this combination performs over a full protocol cycle, see the Halflife case study on multi-compound stacking.
This isn't a marginal difference in features. It's a different category of tool. Shotsy is a health diary. Halflife is a pharmacokinetic level tracker. Both are useful — but only one is useful once your protocol grows past a single weekly injection.
One concern people sometimes raise when switching from a simple app to a more capable one is that it will become complicated to use. That's a fair instinct, and it's one the Halflife — Peptide & GLP-1 Log team thought about carefully.
The visual dashboard is designed to be readable at a glance. You add your compounds once — with their dose, schedule, and administration route — and from that point on, the app does the math. You don't need to understand pharmacokinetics to use it. You just need to be able to look at a screen and know whether your levels are high, mid-cycle, or approaching trough. The app translates the science into a picture that answers the question you actually have: "How much is still in my system right now?"
If you're still on Shotsy because it was the first app you found and it got the job done in the early weeks, that makes sense. That's exactly what it was built for. But if your protocol has grown — more compounds, a custom schedule, a need to understand what's actually happening in your body between injections — you've reached the limit of what a dose diary can offer.
Halflife — Peptide & GLP-1 Log picks up exactly where Shotsy stops. It's built for the users who take their health seriously enough to want real information, not just a timestamp.
Track every compound in your protocol — GLP-1s, peptides, hormones — with real-time level curves, trough alerts, and custom schedules. One dashboard for everything.
Download Halflife — Free on iOS ↗