Quick answer
When I Work publishes a personal calendar link under Calendar Sync, in the top right of the My Schedule page on the web app. Copy the link for Your Schedule, subscribe once on iPhone or Google Calendar, and new shifts appear on their own. Two catches: the Android app cannot generate the link (use a browser at app.wheniwork.com instead), and the Google Calendar phone app cannot add a calendar by link, so that step happens in a browser too. Working a second job, or sharing shifts with a partner? Combine the When I Work link with any other calendar into one link with Calfeed.
When I Work already does the hard part: it publishes a personal calendar link for every schedule. The friction is finding it, and knowing the two places where the obvious path fails.
Find Calendar Sync
Sign in to When I Work in a browser at app.wheniwork.com and open My Schedule. Calendar Sync sits in the top right of the page.
Two things worth naming plainly. The Android app does not offer Calendar Sync at all, so Android users get the link from a browser, not the app. And whichever link you copy is personal: treat it like a password, since anyone holding it can read the schedule.
Pick the right schedule
Calendar Sync offers separate links. Your Schedule carries only shifts assigned to you. OpenShifts carries unassigned shifts you are qualified to pick up. Managers may also see links for an entire location. Most people want Your Schedule.
The link carries published shifts up to a year out. A shift a manager has drafted but not published is invisible to it.
Subscribe on iPhone or Google
On iPhone: open the copied link and confirm when Calendar asks to subscribe. Done.
For Google Calendar: open calendar.google.com in a browser, find Other calendars, choose From URL, and paste the link. The Google Calendar phone app cannot add a calendar by link, so this one step needs a browser, after which the calendar shows up on the phone too.
From then on shifts update on their own. Apple checks about once an hour, Google every 12 to 24 hours. A swap that happens an hour before a shift may not reach the phone in time, which is worth knowing before trusting it blindly.
Two jobs, one calendar
A second job, a class schedule, a partner's shifts: each lives in its own system, and none of them merge on their own. Paste the When I Work link plus any other feed links into Calfeed. It reads every source and republishes one combined link, refreshed hourly, that any calendar app can subscribe to.
That combined link is also the clean way to share shifts at home. A partner subscribes once, without a When I Work login, and sees the schedule stay current.
When Calendar Sync is locked down
Some employers restrict syncing, and some accounts never see the option. The schedule is still on the screen: take a screenshot and paste it into Calfeed's schedule converter. It turns the image into a subscribable calendar in about a minute.