Heavier vs Duo

HEAVIER - AI-Assisted Strength Training Progressive overload for lifters who mean business. Log Your Lifts. Zero Friction. AI analyzes your volume, frequency, and balance. You get the truth: what's working, what's lagging, where you stand. AI coach delivers a daily run-down of your workout, and a daily plan for how to get stronger. Leave your phone in the locker. Tell Siri "Record a lift in Heavier," then dictate your work: "Romanian Deadlift, 3 sets of 10 at 135 pounds." Done. Back to training. Built for lifters chasing strength, not likes.

75 days. Stronger together. Duo is a free challenge tracker for you and your partner. Agree on your rules, check off today’s tasks and see how far the other has got. No subscription, no paywall after setup. TOGETHER OR ON YOUR OWN Start a personal challenge or invite a partner through iCloud. See each other’s check-ins and progress. Share an invitation through WhatsApp, Messages or email. Once your partner accepts your shared plan, the challenge starts for both of you on the same day. TASKS THAT MATCH YOUR PLANS Choose the length and tasks, so a softer version works too. Check off a habit, track an amount or add a personal progress photo. The 75 Hard template includes tasks for two workouts, water, reading, diet and a photo. You confirm workouts yourself; Duo does not record them. SEE YOUR PROGRESS Review your days, tasks and streak, and look back on past challenges. Home Screen and Lock Screen widgets show where you both stand, and the Water widget logs 0.25 L with one tap. Send your partner encouragement or an invitation to walk. NOTIFICATIONS YOU CONTROL Enable reminders and partner notifications and choose your quiet hours. Partner notifications appear after changes arrive through iCloud; timing depends on iOS and your connection. PRIVACY No separate Duo account is needed. Shared challenges and sync require an Apple account with iCloud. You share challenge rules and progress with your partner. Your progress photo stays within the app on your device; your partner only sees whether the photo task is complete. Duo has no ads. Anonymous usage statistics and technical error reports help improve the app. You can turn this off in Settings. APPLE HEALTH Optionally let Duo read your steps from Apple Health after granting permission. Duo does not write data to Health. Available in English, Dutch, German, French, Spanish, Italian, Portuguese, Japanese, Korean and Chinese. Duo is an independent app and is not affiliated with the creators of 75 Hard.