This update sharpens the interface: the iPad layout now uses a centered, comfortable reading width instead of stretching edge to edge, so every screen reads as a clean column. iPhone is unchanged; still fully on-device.

Fathomline 2.0 — a pro upgrade from a logbook to a planner + study suite, still 100% offline. • Minimum-gas / rock-bottom planner: a depth-aware reserve for a buddy pair to surface safely. • Ascent, safety-stop & flying-after-diving planner: ascent-time profile, the recommended stop, and DAN no-fly intervals for single, repetitive, and multi-day dives. • Weighting calculator: a real ballast estimate by exposure suit, water type, and cylinder. • Equipment service tracker with last-serviced and due dates and overdue flags. • Certification & specialty tracker, and a 25-question dive-theory quiz with explanations and scoring. Everything is a planning aid and study tool — not a dive computer, and not a substitute for proper training. No account, no network — everything stays on your device.

Version 1.2 - two substantive new features: CNS OXYGEN TRACKER Every applicable dive now shows an estimated CNS % on the dive detail screen, calculated from the NOAA single-exposure table (the same table used in every Enriched Air course). See your ppO2 at working depth, the NOAA time limit for that gas, and how close you are to the 80 % single-dive working limit. CNS exposure is shown for nitrox dives and for deep air dives that reach the table range (ppO2 0.6 bar and above). The Tools tab adds a full interactive CNS calculator - enter any gas and depth to get the exposure estimate and the complete NOAA reference table at a glance. The Stats screen shows your total accumulated CNS % across all logged dives where a CNS reading applies. MILESTONES A new Milestones card on the Stats screen tracks six categories of personal achievements: total dives (10, 25, 50, 100, 200, 500, 1000), cumulative bottom time (10, 25, 50, 100, 250 hours), depth reached (18, 30, 40 m), distinct sites visited, nitrox dives, and night dives. Each earned milestone shows a gold checkmark; upcoming milestones show a progress bar so you always know how close you are. All new features are fully offline. CNS tracking is clearly presented as an educational reference - not a real-time dive computer.

Version 1.1 — three substantial new features, all fully offline: REPETITIVE DIVE PLANNER An interactive PADI RDP reference built into the Tools tab. Enter your first dive (depth + time) to see your exit pressure group, then dial in your surface interval to find your new group, and plan your next dive with the correct adjusted no-decompression limit (ANDL) and residual nitrogen time (RNT). Includes an NDL quick-reference table for all recreational depths. Always shown with a clear training disclaimer — this is an educational study aid, not a dive computer. SITE NOTEBOOK A personal notebook for dive sites you return to. Store typical depth, visibility, water temperature, a star rating, and your own notes. Linked to your logged dives at that site — tap any entry in the notebook to see your full dive history there. Access from the Logbook tab (top-left mappin icon). PDF LOGBOOK EXPORT Export your entire dive logbook as a formatted PDF — diver profile, summary statistics, a full dive table and a diver/instructor signature block. Perfect for showing a liveaboard, dive shop, or course instructor your experience at a glance. Find it in Settings → Your data → Export PDF logbook.