--- title: "Peptide Library vs PepTracker: AI Protocols or Research and Vendor Comparison?" canonical_url: https://peptidelibrary.app/compare/peptide-library-vs-peptracker description: "PepTracker pairs protocol tracking with AI on iPhone. Compare it with Peptide Library on research, vendors, platforms, inventory and price." updated: 2026-10-25 publisher: Peptide Library notice: "Research and educational use only. Not medical advice." --- # Peptide Library vs PepTracker: AI Protocols or Research and Vendor Comparison? Protocol management, AI summaries, calendar sync and research tools compared, with where each app is ahead. ## Quick verdict PepTracker is an iPhone protocol manager: stacked and cycling protocols, due, upcoming and missed reminders, Apple and Google Calendar sync, two-way Apple Health, and AI (PepGuide and PepPulse) that builds a protocol from a sentence and sums up your week. Peptide Library goes further on research and buying, with cited profiles, publication data and vendor price comparison, and it also runs on Android and the web. ### Choose Peptide Library if - You use Android or want a web app; PepTracker is on iPhone. - You want profiles that cite their studies, plus publication and trial statistics per peptide. - You compare vendor listings and price per mg. - You want progress photos and injection-site rotation, which PepTracker's listing doesn't mention. ### Choose PepTracker if - You want AI to set up protocols and summarise your consistency, mood and energy. - You want reminders in Apple Calendar or Google Calendar. - You want weight, body fat and waist synced both ways with Apple Health. - You want stacked protocols with starter and advanced templates. ## Key differences ### AI-assisted protocols, or none PepGuide builds protocols and reminders from a sentence or a photo of your plan, and PepPulse summarises your week; both are Premium. Peptide Library has no in-app AI. ### Platforms PepTracker is an iPhone app; its website shows a Google Play badge with no link. Peptide Library has iPhone and Android apps and a web app. ### Research and vendors PepTracker includes a peptide library without a published count. Peptide Library adds cited references, research statistics and vendor price comparison. ### Progress tools PepTracker tracks weight, body fat, lean mass and six body measurements, with goals. Peptide Library tracks body metrics too and adds progress photos, journal check-ins and injection-site rotation. ## Research PepTracker ships a built-in peptide library, and PepGuide answers general questions about peptides by text or photo. The listing doesn't describe research references or a profile count. Peptide Library's 200+ profiles cite PubMed, ClinicalTrials.gov, DailyMed and EMA sources, with studies labelled by evidence type. Its Research Intelligence Center adds publication and trial statistics, and Compare puts two or three peptides side by side. ## Tracking PepTracker schedules daily, twice-daily, weekly, twice-weekly, monthly, cycling, every-other-day and every-X-days doses, runs several compounds in one stacked protocol, and keeps protocol history you can restore. Its calendar has month and hour-by-hour week views, and reminders can appear in Apple or Google Calendar. Peptide Library's schedules cover every day, chosen weekdays, every N days, on/off cycles, several times a day and titration; past days keep the schedule they had when you edit one. Its calendar shows taken, missed and skipped doses by month or week. For supplies, PepTracker shows doses and days left per vial with a refill reminder. Peptide Library deducts stock when you log and adds run-out and reorder-by dates and low-stock and expiry alerts. ## Vendors PepTracker doesn't advertise vendor listings or price comparison. Peptide Library's Shop compares vendor listings by compound and product form, shows price per mg after any coupon code, and links to vendor profiles with reviews. ## Pricing PepTracker's free plan covers up to 3 protocols, logging, reminders, supply tracking, calendar sync, the library and 30 days of weight history (its website says 2 protocols). The App Store lists Premium at $7.99 a month, $47.99 a year and $79.99 to $99.00 for lifetime, with a 7-day trial on the annual plan. Peptide Library Pro is $4.99 a month, $39.99 a year or $89.99 once. ## Where PepTracker is stronger ### AI that builds and reviews protocols Describe a protocol in one message, ask about your own logs, and get a weekly recap of consistency, mood and energy. ### Calendar sync Doses appear in Apple Calendar or Google Calendar, alongside the rest of your day. ### Two-way Apple Health Weight, body fat and waist sync both ways. Peptide Library reads weight and body fat and never writes. ### Templates and stacks Starter and advanced protocol templates, with several compounds in one stacked protocol. ## Features | Feature | Peptide Library | PepTracker | |---|---|---| | iPhone app | Yes | Yes | | Android app | Yes | Not advertised | | Web app | Yes, installable | Not advertised | | Free plan | Yes (inventory: 1 peptide) | Up to 3 protocols | | Dose logging | Yes | Yes | | History and calendar | Yes | Yes | | Recurring schedules | Yes | Yes | | Reminders | Yes | Yes | | Cycles and titration | Yes | Yes | | Vial inventory | Yes (free: 1 peptide) | Supply tracking | | Low-stock or run-out alerts | Yes | Yes | | Expiry dates | Yes | Not advertised | | Stock deducted on logging | Yes | Not advertised | | Compound library | 200+ profiles | Yes (no count published) | | Cited research references | Yes | Not advertised | | Publication and trial data | Yes | Not advertised | | Community research trends | Yes (full view with Pro) | Not advertised | | Vendor directory | Yes | Not advertised | | Vendor price comparison | Yes | Not advertised | | Price per mg | Yes | Not advertised | | Vendor reviews | Yes | Not advertised | | Reconstitution calculator | Android and web | Removed from the app | | Estimated level charts | No | Not advertised | | Weight and body metrics | Yes | Yes | | Progress photos | Yes (free: up to 2) | Not advertised | | Journal or symptom check-ins | Yes | Yes | | Injection-site rotation | In the apps, not on the web | Not advertised | | Nutrition tracking | No | Not advertised | | Community | Discussions free; Q&A with Pro | Not advertised | | Apple Health | Yes | Two-way sync (Premium) | | Health Connect (Android) | Yes | Not advertised | | Wearables | No | Not advertised | | Home Screen widgets | iPhone only | Not advertised | | AI assistant | No | PepGuide and PepPulse (Premium) | | Multi-device sync | Pro (free Android accounts sync most data) | Premium | | On-device storage | Yes | Not advertised | | Data export | Pro | CSV (full history with Premium) | ## Final verdict PepTracker is a strong protocol manager for iPhone users who like AI help and calendar integration. Peptide Library is the better choice when you need Android or the web, or when research and vendor comparison sit alongside your tracking. Both offer a free tier and a lifetime purchase, so you can try each before committing. ## Frequently asked questions ### Does PepTracker have a calculator? Not in the app any more. Its release notes say the Calculator tab was removed to meet App Store guidelines, and the listing says it doesn't calculate doses. Its website still links a web dose calculator. Peptide Library's calculator is on Android and the web. ### Is PepTracker available on Android? Not as of October 2026: its website shows a Google Play badge with no link, and we found no Play listing. Peptide Library is on iPhone, Android and the web. ### How much is PepTracker Premium? The App Store lists $7.99 a month, $47.99 a year, and $79.99 to $99.00 for lifetime, with a 7-day trial on the annual plan (US, checked October 2026). Its website shows $4.99 a month as a discounted price. ### What are PepGuide and PepPulse? PepTracker's Premium AI features. PepGuide builds protocols and answers questions about your logs; PepPulse summarises consistency, mood and energy trends, with Apple Health vitals. ### Does PepTracker compare vendor prices? Not according to its listing or website. Peptide Library's Shop compares vendor listings and price per mg within each product form. ### Which app works with Apple Health? Both. PepTracker syncs weight, body fat and waist both ways with Premium. Peptide Library reads weight and body fat from Apple Health or Health Connect and never writes to them. Comparisons use public listings and websites. "Not advertised" means no source we checked mentions the feature, not that it is missing.