Every expense tracker wants your bank login before it draws a chart. Gravity has no account and no server — everything stays on your phone; the only network call fetches exchange rates. What's different: one number each morning (what's safe to spend today, after bills), logging from Siri and widget buttons, UPI screenshots read on-device, and bill splitting where friends never need the app — the card goes to WhatsApp with your UPI ID. Free, no ads, no upsell. iPhone now, Android next.