Lists that crown a single winner are usually written by the winner. Here's the split by what you're actually trying to do.
Pick by what you're sharing
| You want to... | Use | Free tier | Costs |
|---|---|---|---|
| Coordinate with one partner | Cupla | All features, limited time window | Premium unlocks full window |
| Run a household with kids | Cozi | Full calendar, with ads | Gold $39 |
| Keep several groups separate | TimeTree | Multiple calendars, comments, photos, imports | $4.49/mo or $44.99/yr |
| Add nothing new | Google Calendar | Everything | Free |
| Handle a shift rotation and the drive | BoardSpy | 1 rotation, 1 calendar, 2 people incl. you | Basic $2/mo · Pro $5/mo · $50/yr · $100 once |
Prices checked 15 October 2026 against each vendor's own pages, linked below. TimeTree's figures are from its 2022 pricing announcement, the most recent on its own site.
Cupla — two people, nothing else
Cupla is built for exactly two partners, and the narrowness is the feature. No family mode to skip past, no team invites.
Its own facts page says every feature is on the free tier, with Premium unlocking the full viewable time window rather than locking features away. You get a shared calendar, shared to-dos, a date planner, key dates and wishlists.
The part that matters most is the two-way sync with Google, Apple and Outlook. One-way sync means the app can show you what's in your calendar but anything you create in the app never reaches the calendar you actually open. Two-way means it does.
iOS, Android, and a web app in beta since May 2026.
Not for you if: you need a third person. Cupla connects two by design.
Cozi — a household, not a couple
Cozi is a family organiser that happens to include a calendar: shopping lists, meal planning, to-dos, colour-coded members.
The free version is ad-supported. Cozi Gold is $39 and adds ad-free use, month view on mobile, calendar search, up to three reminders per event, change notifications, a birthday tracker and shopping mode. Cozi doesn't publish a member cap.
Not for you if: there are two of you and there always will be. You'll use a fifth of it.
TimeTree — several groups at once
TimeTree's advantage is that you can run more than one shared calendar: one with your partner, another with a sports team, another with your siblings, kept separate.
TimeTree's support page lists the free features as creating and sharing calendars, running several, comments and photos on events, importing other calendars and using public ones. Premium is $4.49 a month or $44.99 a year as announced in April 2022, mostly for ad removal and support.
For a free tier, that's unusually complete.
Not for you if: you want the calendar to prompt you rather than display to you.
Google Calendar — the one you already have
If everyone involved is already in Google, sharing a calendar costs nothing and takes a minute. It syncs everywhere, it's already on your phone, and there's no new account.
What you lose is anything designed for a specific relationship — shared to-dos, a view built around "what are we both doing", anything that understands the group rather than the individual. You're using a work tool for a home job.
For plenty of people that's genuinely fine, and a page that pretends otherwise is selling you something.
Apple Calendar — fine if everyone has an iPhone
Shared iCloud calendars work well and cost nothing. The catch is the obvious one: everyone you're sharing with needs to be on Apple. One Android phone in the group and you're back to a third-party app.
BoardSpy — a shift rotation and the drive to work
Ours, so the limit first: the free shared calendar holds 2 people including you. A third needs Pro. Know that before you install.
What no other app here does: the alarm is timed to live traffic on the actual route. Everything else on this page rings at a time you chose. BoardSpy asks Google Maps how long the drive is right now and rings at shift start minus drive time minus a five-minute buffer, so the leave-by time moves with the road. The lead time you set is only the fallback when there's no drive time available.
The second thing: shift rotations are named presets — DuPont, Panama, 2-2-3 / Pitman, 4 on 4 off, 4 on 4 off rotating, D-D-N-N-O-O, 5-2, 24/48 and 48/96. Tap one, set a start date, and it fills 120 days ahead. There's a Kelly-day field for firefighters, every Nth working shift, 2 to 30. Custom cycles go up to 56 days.
Basic is $2/month for unlimited calendar alarms, still two people. Pro at $5/month, $50/year or $100 once adds the third member, more rotations, phone-calendar export and the lock-screen countdown. After the seven-day trial a free account keeps the calendar but the alarms stop.
Not for you if: you both work regular hours and just want to see each other's week. Use Cupla.
The three questions that actually decide it
How many people fit on the free tier? This is what bites, because you find out at the moment you try to add someone. Cupla is two by design. BoardSpy is two including you. Cozi and TimeTree don't publish a number.
Does the sync write back? A read-only mirror shows your partner what's in your calendar. It doesn't put a shared event into the calendar you check each morning. Cupla is two-way with Google, Apple and Outlook. BoardSpy's Google mirror is read-only, and on iPhone Apple Calendar is used for alarms rather than mirrored.
Does it remind you, or just show you? Most of these are a shared view. If the problem is that you both forget, a view doesn't solve it.
What about the ones we left out
OurCal, Howbout and Motion all turn up in these searches. They're not in the table because we couldn't verify their current terms from their own sites, and a comparison that guesses at a competitor's free tier isn't worth reading.
Frequently asked questions
What is the best shared calendar app?
There isn't a single one. For two people, Cupla. For a household with kids, Cozi. For keeping several groups separate, TimeTree. If everyone's already in Google, Google Calendar is free and takes a minute. If one of you works a shift rotation and the commute is the problem, BoardSpy.
What is the best free shared calendar app?
TimeTree and Cupla have the most complete free tiers — TimeTree gives you multiple shared calendars, comments, photos and imports at no cost, and Cupla puts every feature on free with a limited time window. Google Calendar is free outright if you're already in Google.
Can I share a calendar between iPhone and Android?
Yes, with a third-party app. Cupla, TimeTree, Cozi and BoardSpy all run on both. Sharing an Apple Calendar directly requires everyone to be on Apple devices, which is the usual reason mixed-phone households end up on something else.
How many people can share one calendar?
It varies and it's often not published. Cupla is built for two. BoardSpy's free shared calendar is two including you, with a third requiring Pro. Cozi and TimeTree don't state a cap on their own pages. Check before you build a routine around one.
Do shared calendar apps sync with Google Calendar?
Most read from it; fewer write back to it. Cupla syncs two ways with Google, Apple and Outlook. BoardSpy mirrors Google events into a shared calendar read-only and never writes to your Google calendar. The difference matters if you want events created in the app to appear in the calendar you already use.
Will a shared calendar app tell me when to leave?
Almost none will. They show what's scheduled and remind you at a time you set. BoardSpy is the exception on this list: it times the alarm to the live traffic drive time on your route plus a five-minute buffer, so the leave-by time changes as the road does.