Zero vs Fastic vs Swoodie 2026: The Best Intermittent Fasting Apps Compared

Intermittent fasting has settled into the mainstream, and three apps keep showing up at the top of the lists: Zero, the brand most people name when you say “fasting app”; Fastic, which pairs a fasting timer with a recipe library and a calorie scanner; and Swoodie, which added a fasting tracker, a fasting coach and partner sync in v1.4. All three will time your eating window. They are not the same product around it.

This is the honest comparison — what each app is genuinely best at, and which one fits the way you actually fast.

The 60-second verdict

• Pick Zero if you want a polished, single-purpose fasting timer and the brand reputation that comes with years in the category.
• Pick Fastic if you want fasting plus a recipe library and a generous free AI food scanner in one app.
• Pick Swoodie if you want fasting plus a full recipe and meal-planning app, with the option to sync your window with a partner.

How we compared them

Pricing and feature figures below come from each app’s own listing, checked in 2026. We focused on what App Store screenshots tend to skip: how usable each free tier really is, and what the app gives you the rest of the day, when the timer isn’t running.

Free tier: the real differentiator

A fasting timer is a simple thing. The question is what each app gates behind a paywall around it.

• Zero: a free fasting timer with the standard preset protocols (13:11, 16:8, 18:6, 20:4, and similar). Advanced plans, mood tracking, custom protocols, journaling and richer history sit behind Zero Plus.
• Fastic: an unusually generous free tier — the AI food scanner works without paying, the phase-by-phase timer is free, and you get access to the recipe library. Advanced features and the deeper plans sit on Fastic Plus.
• Swoodie: the fasting tracker itself is free, with all six protocols (12:12, 14:10, 16:8, 18:6, OMAD, custom), a live timer and history. The full 8,000+ recipe library and basic meal tracking are also free with no account. Fasting Coach and Fast Together (partner sync) are Premium; AI features come as a 5-use free trial, then Premium.

For pure fasting, all three are free enough to actually use. Fastic stretches the free tier furthest into AI territory; Swoodie stretches it furthest into recipes and cooking.

Protocols and the timer experience

Zero has had years to polish a single screen. The timer is calm, the protocol picker is fast, and the long-term history view is one of the better ones in the category — exactly what you would expect from the app that defined the genre.

Fastic wraps the timer in narrative — a phase-by-phase view that explains what your body is supposedly doing as the hours pass — and offers a distinct Protein Fasting mode alongside the standard 16:8 and 18:6 protocols. If you find the “what is happening right now?” framing motivating, it is genuinely well done.

Swoodie ships six protocols (12:12, 14:10, 16:8, 18:6, OMAD, custom) with a live timer and history, and adds Ollie’s Fasting Coach on Premium — small nudges, milestone notes and the occasional well-timed quip inside the window. The timer itself is simple by design; the personality is the optional upgrade.

Beyond the timer: what else each app does

This is the second-app question. A fasting timer counts down hours. It doesn’t help you decide what to eat when the window opens, what your calories looked like across the day, or what to cook tomorrow.

• Zero: fasting only. No recipes, no meal planning, no calorie tracking, no shopping list. If you want any of those, you will be running a second app.
• Fastic: fasting plus a 4,500-recipe library, the AI food scanner and a calorie tracker. One app instead of two for most fasters.
• Swoodie: fasting plus the full kitchen — 8,000+ recipes, AI recipe generation (Chef AI), an AI meal planner, an auto shopping list, calorie and macro tracking, photo and barcode logging, Swipe Together for couples and Nest for households.

If fasting is the whole story for you, Zero’s focus is a feature. If fasting is one piece of a larger eating plan, Fastic and Swoodie cover more ground in one app.

Fasting together with a partner

This is the section where the three apps diverge most sharply.

• Zero: no partner feature. You can compare notes outside the app, but the timer itself is yours alone.
• Fastic: “Fasting Buddies” — a social layer with challenges and community, useful for accountability but not a synced clock between two specific people.
• Swoodie: Fast Together — a real synced window. Host an invite (Premium) and your partner joins for free; both timers show the same start, the same end, the same milestones inside the window.

The difference is small in theory and large in practice. A shared community keeps you motivated in general; a synced window means you and one specific person break the fast at the same minute. For couples and accountability pairs, that is a different kind of habit.

Pricing: and the two-year picture

• Zero Plus: a subscription on top of the free timer.
• Fastic Plus: $14.99/month or $79.99/year.
• Swoodie Premium: $9.99/month or $39.99/year, with a 3-day trial on the annual plan and a $3.99 weekly option.

Over two years Swoodie Premium runs about $80 versus around $160 for Fastic Plus — and Swoodie is the broader app of the two, with the full recipe and planning stack on top of fasting. Zero’s subscription sits between them and only gets you the fasting half. For most fasters, the question isn’t whether to pay; it is which annual price you are paying for which surface area.

Where Swoodie falls short

In fairness: Zero defined this category and has years of polish, a loyal user base and the kind of brand reputation a v1.4 fasting tracker simply cannot claim — if you want the “fasting app everyone has heard of,” that is Zero. And Fastic’s “Fasting Buddies” community has real, established usage; a brand-new partner-sync feature is not a substitute for an active community you already know. Swoodie’s case is breadth — fasting inside a full kitchen app, with a synced window for the one person you actually fast with — not being the most established fasting-only brand in the App Store.

Which one for your goal?

• Pure fasting, polished single-purpose app: Zero.
• Fasting plus a generous free AI food scanner: Fastic.
• Fasting plus recipes, meal planning and tracking in one app: Swoodie.
• Fasting with a partner on a synced clock: Swoodie — Fast Together is unique here.
• Lowest annual cost for the broadest feature set: Swoodie — $39.99/year.

A quick scenario

The couple starting 16:8 together. You both want to try intermittent fasting, but the moment one of you eats at 11 and the other at noon, the “we’re doing this together” story falls apart. Zero will time each of you separately. Fastic will put you in the same community. Swoodie’s Fast Together gives you both the same window on the same clock, with the same recipes ready when it opens: which is what “together” was supposed to mean.

Deeper one-on-one breakdowns

Swoodie vs Fastic · All alternatives

More on fasting: MyFitnessPal vs Yazio vs Swoodie for calorie-counter perspective, Yazio vs Lifesum vs Simple vs Swoodie for fasting + wellness apps, and the intermittent fasting use case page.

Try Swoodie free on iOS or Google Play — no account needed; fasting tracker is free, AI features have a 5-use free trial, no card.