On-call alerts without PagerDuty: a phone call for P1s when you are a team of three
Running a rotation? Use PagerDuty. If you are one to three people whose alerts land in Gmail and Slack, here is how to get a real phone call for a P1 alert.
If you have an on-call rotation, stop reading and set up PagerDuty, or Better Stack, or whichever paging tool your team already half-uses. Those tools own schedules, escalation and acknowledgement, and nothing cheap replaces that. This post is for the other case: you are one person, or three, every alert you care about already lands in Gmail or Slack, and your phone goes "ding" for an outage exactly the way it does for a Jira comment.
OLL.E does none of the PagerDuty things. It reads Gmail and your Slack notifications for whatever you call an incident, and phones you. On iPhone the Gmail half works with nothing extra; the Slack half needs the PinG keyring. If you just thought "but who takes the call when I am on a plane", you have a rotation, and you already know what to buy.
Do small teams need PagerDuty?
Not when nobody is handing the pager to anybody. PagerDuty's value is the chain: it knows who is on this week, pages them, and if nobody acknowledges, it pages the next person. A team of three where the same person always answers has no schedule to run.
The free plan is generous for a team that size: up to 5 users, one on-call schedule, one escalation policy, and 100 SMS or phone notifications a month. Professional is $21 a user a month billed yearly ($25 monthly). If every alert you care about comes from a monitor you can point at PagerDuty, try the free plan before anything else in this post. It gets harder when the alert is a person. A customer writes "the site is down!!", or your co-founder asks "umm is prod ok?" in Slack. No monitor sent those, and in our experience they are the incidents small teams see late.
Opsgenie used to be the other cheap answer. Atlassian stopped selling it to new customers in 2025 and is moving existing customers to Jira Service Management and Compass.
The cheap setup is honestly fine for a solo founder whose side project makes money, for two or three people who have agreed out loud that one named person answers nights, and for a small agency whose client says "the site is down" by email as often as a monitor does.
How do I get a phone call for a critical alert?
Four ways without a paging tool.
The first is your monitor's own call. UptimeRobot phones you on any paid plan; the cheapest, Solo, is $9 a month billed yearly, and each call spends credits rather than coming out of a monthly quota. Better Stack's free plan alerts by email and Slack only, and unlimited calls and SMS come with its Responder licence at $34 a month. Either is the simplest answer if that monitor is your only incident source.
Your phone's own exceptions cost nothing. On newer Android, open Settings > Modes, pick a mode, then Notification filters, and choose which people, apps and alarms still get through (Google says the menus vary by phone, and older versions call it Do Not Disturb). On iPhone it is Settings > Focus, pick a Focus, then People or Apps. The catch is that letting Gmail through lets every email from that account through with the outage, and it is still just a notification.
Pushover costs $4.99 once per platform, after a 30-day free trial. It sends a push, not a call, and something upstream has to fire it.
IFTTT's Phone Call service has a "Call my phone" action that rings you and reads a short message aloud. It needs a Pro plan ($5.49 a month billed yearly) and a US number, and stops at 100 calls a month. More in the Zapier vs IFTTT post.
Or something reads the message for you, which is where OLL.E sits. You type what an incident is in your team's words, it checks Gmail and Slack notifications for a match, and it phones you.
| PagerDuty | Your monitor's own calls | Pushover | OLL.E | |
|---|---|---|---|---|
| Rotation and escalation | Yes, this is the product | No | No | No |
| Phone call | Yes; Free includes 100 SMS/phone notifications a month | Yes, on paid plans | No, a push | Yes, or an alarm |
| Works from email and Slack | Through integrations you set up | No | Only what you wire to it | Yes, both are sources |
| From price | Free up to 5 users; Professional $21/user/mo yearly | UptimeRobot Solo $9/mo yearly (calls use credits); Better Stack Responder $34/mo | $4.99 once per platform, 30-day trial | Free plan, 4 watches; Pro $19.99 a month |
Can Slack call me?
No. You can add keywords in Slack's notification preferences, and a message with one in it gives you an ordinary notification. On iPhone you can let Slack through a Focus under Settings > Focus > Apps, though then every Slack notification gets through, the #random jokes included.
To turn a Slack message into a call, something outside Slack has to read the notification and dial. On Android, OLL.E does that with notification access. iPhone doesn't let apps read other apps' notifications in the background, so there the Slack watch needs PinG, a Bluetooth keyring that relays notifications and rings on its own speaker.
What about UptimeRobot, Grafana and Sentry emails?
Those tools all email, and to a keyword filter a "resolved" email looks a lot like a "down" one. Three watches cover most of it, each modelled on the production down watch.
The call
Start with the one that wakes you: "Call me if 'production down', 'P1' or 'customers can't log in' hits my inbox or Slack." It phones you and summarises the thread, so the call comes with the three lines you would otherwise read standing in the kitchen. Use your team's actual words. If incidents start with someone typing "uh oh" in #eng, put "uh oh" in the sentence. OLL.E reads the message rather than matching the string, so "P1 scheduled for next sprint" in a planning thread should not ring. Expect to reword it a few times.
The monitors
Monitor emails get an alarm, on purpose. A call for every flap trains you to decline calls. Type "Alarm me when a Sentry, UptimeRobot or Grafana email says a service is down or the error rate is up" and add a Gmail label as the action. Gmail is the only source, so this one works fully on iPhone. A "resolved" email isn't what the sentence asks for; if you want those collected for the morning, give them their own watch with the Shortlist as the alert.
The hand-off
"When an incident email arrives, forward it to my co-founder and send me a summary." This one goes to the Shortlist, since the first watch already rang, and because actions chain, one watch does both jobs. It is the nearest a cheap setup gets to a second responder, minus the acknowledgement.
Then test it: email yourself "production down" from another account. If the phone stays quiet, check the phone before the watch. Whether OLL.E's call or alarm gets through Do Not Disturb or a Focus is the phone's decision. On Android, allow OLL.E's calls under Settings > Modes, pick the mode, then Notification filters. On iPhone, add them under Settings > Focus > People. With PinG paired to an iPhone, the keyring also rings on its own speaker.
What does a cheap on-call setup miss?
Two things. Decide you can live with both before you skip the paging tool.
The first is you: a flat battery, airplane mode after a late flight, the flu, a week off. PagerDuty notices the unanswered page and moves to the next person. OLL.E has no next person, because you never gave it a list. The hand-off watch puts the email in front of a colleague, but it cannot make them wake up, and it cannot tell you they did.
The second is acknowledgement. Pressing Ack in a paging tool tells everyone else you have it. Without that, two of you fix the same thing at 3 am, or each assumes the other is on it. For three people a group text saying "on it" covers this.
Somewhere past five or six, it stops working.
My view: if nobody hands the pager to anyone, set up the call this week and move to PagerDuty the day you write your first on-call schedule. Small teams often keep a paging tool trial open in a tab for months while the real incidents arrive by email and get read the next morning.
For a team without a rotation, OLL.E is the part that reads the incident email or Slack message and phones you. You type "Call me if 'production down' or a P1 alert hits my inbox or Slack", and the call comes with a summary of the thread. It does not do rotations, escalation or acknowledgement. A free plan covers a small setup like this one, no card. Pro is $19.99 a month with a 7-day trial. On iPhone, Gmail works as is; Slack needs the PinG keyring, sold separately.
Questions people ask
Is there a free alternative to Opsgenie for a small team?
PagerDuty's free plan is the obvious one: up to five users, one schedule, one escalation policy and 100 SMS or phone notifications a month. Opsgenie itself is no longer sold to new customers, as Atlassian moves people to Jira Service Management and Compass. If all you need is a call when an incident email or Slack message arrives, OLL.E's free plan covers four watches.
How do I get a phone call when my site goes down?
Turn on your monitor's voice alerts if it has them. UptimeRobot includes calls on paid plans from $9 a month billed yearly, paid for with credits, and Better Stack gives unlimited calls with its $34-a-month Responder licence. When the alert arrives as an email or a Slack message instead, you need something that reads it and dials, such as OLL.E, or IFTTT's Call my phone action if you have a US number and a Pro plan.
Can Slack make my phone ring for a critical alert?
No. A Slack keyword match is an ordinary notification. To get a call, another app has to read the notification and phone you: on Android OLL.E does this with notification access, and on iPhone it needs the PinG keyring, because iOS keeps other apps' notifications away from background apps.
What does PagerDuty do that a cheap on-call setup cannot?
Rotations, escalation and acknowledgement. PagerDuty knows who is on call, pages the next person when nobody answers, and shows everyone when someone has taken the incident. A cheap setup calls you and has nobody to try after you.