ReefBuddy vs Derive

Stop guessing. Start thriving. Your reef tank deserves better than guesswork. ReefBuddy logs your water chemistry, shows you the trends, and uses AI to turn your test results into clear, specific recommendations, so you can focus on watching your corals grow. AI-POWERED ANALYSIS Enter your water parameters and tap Analyze. In seconds you get a plain-English summary, warnings first, specific recommendations and dosing amounts worked out for your tank's volume and type. No more forum diving or conflicting advice. TRACK EVERYTHING Log temperature, salinity, pH, alkalinity, calcium, magnesium, nitrate, phosphate, ammonia and nitrite. Every field shows its healthy range as you type. Log water changes alongside your tests so you can see what each one did. TREND CHARTS See any parameter charted against its healthy range, from the last week to the last year. Spot the slow drift weeks before your corals show it. LIVESTOCK MANAGEMENT Catalogue your corals, fish and invertebrates with photos, species, purchase details and a health log timeline. Track recovery, not just losses. MAINTENANCE REMINDERS Schedule water changes, filter service and testing, every N days or on set weekdays. Your phone reminds you. MULTIPLE TANKS Display, frag tank, quarantine, nano. Seven tank types, each with its own history, livestock and reminders. YOUR DATA, YOURS Export any date range to CSV and send it to a spreadsheet, an email or your local fish store. BOLD DESIGN A high-contrast, New Brutalist interface built to be read at arm's length with wet hands. No clutter. Just the information you need. FREE TO USE, NO SUBSCRIPTION Logging, charts, livestock and reminders are free. AI analysis includes 3 free analyses per device, then credit packs of 5 or 50. Credits never expire. No account required. Whether you are a seasoned reefer or starting your first nano tank, ReefBuddy gives you the confidence to keep your reef healthy, stable and thriving.

Derive Notes is a canvas-first note-taking app built for math, science, and engineering students. Write equations by hand with Apple Pencil, and let Derive understand what you wrote, so your notes do more than sit on the page. HANDWRITING THAT'S ACTUALLY UNDERSTOOD Draw on an infinite canvas the way you would on paper. Derive recognizes your handwritten math as you work, turning messy strokes into clean, structured expressions you can check, reuse, and build on. A TUTOR RIGHT NEXT TO YOUR WORK Stuck on a step? Open the tutor panel and get step-by-step help tied directly to what's on your canvas. It works alongside your handwriting instead of pulling you into a separate app. BUILT FOR REAL STUDY SESSIONS - Infinite canvas with smooth, low-latency inking - Pen, eraser, and lasso tools for fast editing - Organize your work into notebooks and pages - Two-finger tap to undo, pinch to zoom - Your notebooks sync securely across your devices DESIGNED FOR FOCUS A clean, distraction-free workspace with light, dark, sepia, and high-contrast themes, so long study sessions stay comfortable. Derive Notes keeps your handwriting at the center and adds just enough intelligence to make studying faster by recognizing your math, helping you through hard steps, and keeping every page organized and in sync. Note: Derive uses trusted third-party AI providers to process handwriting and page text for recognition and tutoring. You're asked for consent in-app before these features are used. DESIGNED FOR IPAD AND APPLE PENCIL Handwriting, drawing, and the full authoring tools require an iPad with Apple Pencil. On iPhone, Derive is a companion for reading and reviewing your notebooks: browse your library, open any page, search across everything, and ask the tutor. Notes you write on iPad appear on iPhone automatically. SUBSCRIPTION Derive Pro unlocks writing and editing, handwriting recognition, and the AI tutor. Every new account starts with a 7-day free trial, and a trial or subscription is required to use Derive. If a subscription later lapses, the notebooks you already made stay readable, so your own work is never locked away. - Derive Pro Monthly: A$9.99 per month - Derive Pro Annual: A$101.99 per year - Both start with a 7-day free trial Prices are in Australian dollars and may vary by region. Payment is charged to your Apple Account at confirmation of purchase. A subscription renews automatically unless auto-renew is turned off at least 24 hours before the end of the current period, and your account is charged for renewal within the 24 hours before that period ends. You can manage your subscription and turn off auto-renew in your Apple Account settings after purchase. Any unused portion of a free trial is forfeited when you buy a subscription. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Derive Terms of Service: https://derivenotes.com/terms Privacy Policy: https://derivenotes.com/privacy