“I would like to recommend SIGNL4. We have connected it to our Operations Manager environment so we can be as pro-active as possible, leading to less downtime of disrupted services.”



Solution Architect / ASAPCloud


Critical Alert Notifications that Work

SIGNL4 is an out-of-the-box cloud solution that enables operations and business teams to respond faster and more effectively to critical alerts, major incidents and urgent service requests. SIGNL4 reliably delivers the right information to the right people at the right time – anywhere. It notifies active staff on duty through targeted and persistent mobile push, text and voicecalls with acknowledgement, tracking and escalation. SIGNL4 enables technical systems in IoT, on the shop floor and in hundred other areas to connect and communicate with the right people.


A new Mobile Alerting Experience

SIGNL4 focuses on the essence of critical alerting and service dispatching. It has been especially designed for critical operations and features for instance a native ‘darkmode’. It is lightweight but very effective. SIGNL4 is a modern B2B app – visual and easy to use.

Mobile Alert Management

Never miss a critical Alert

SIGNL4 notifies your team members on duty persistently by push, text and voice call until an alert is acknowledged and confirmed by a single or multiple persons. If there is no response within a certain time (“target response time”), team managers will be notified automatically.

Persistent Notifications

Alerting on your terms

SIGNL4 provides for an unrivalled notification experience. Define the sequence of push, text and voice calls. Choose the ringtone that is most effective. Enable persistent notification for your team and select the proper channel. And override the hardware mute button on your iPhone.

Notification Pattern

Alert Routing & Duty Management with a single Touch

Team members can go on and off duty with a single touch. The SIGNL4 duty assistant reminds on duty hand-overs. All hours spent on duty are automatically logged and reported. Once users checked in for duty, alerts are automatically routed to them. If they are not on duty, they won’t get alerted.

Automated Alert Routing

Duty & Shift Scheduling in your browser

Conveniently schedule your team’s shifts and on-call duties from any webbrowser and with a few mouse-clicks and drag&drop. SIGNL4 scheduling covers any scenario. It comes with minimum staffing level monitoring and post-shift reports for a digital hand-over.

Scheduling in SIGNL4

Tracking and Ownership

SIGNL4 provides for alert ownership transparency. Alert confirmations and annotations are visible in real-time throughout the entire team avoiding waste and following up on who takes care of what.


Rich and Augmented Alerts

Enrich your alerts with great content including text parameters, images, sound files, weblinks and maps. Either use the open APIs to deliver your content or use the built-in capabilities to augment alerts with text, color, icon, maps and push sound.


Anywhere Collaboration

SIGNL4 provides a unique incident-related mobile chatops feature for anywhere collaboration. Each alert creates a persistent chat room and team members chat and share annotations in real-time. So, everybody can contribute from anywhere to solving a critical problem or incident.

Shared mobile Annotations

Connect your Systems with Ease

Integrates seamlessly with hundreds of applications (see our growing list here). On top, each team has an associated, dedicated email address you can use to raise alerts. Or use the webhook or REST API to connect any system. And as SIGNL4 is a cloud solution, you can simply download the app and you’re good to go.


Customize and personalize

You can customize SIGNL4 to meet your individual alerting needs and to create actionable alerts. And personalization options make SIGNL4 even more powerful. Choose custom notifications sounds, upload a personal picture and a team picture to make it ‘your’ SIGNL4.


* Features can be subject to a chosen plan

Start a 30-Days Test-Drive

SIGNL4 explained in 8 minutes

Mobile Alerting with SIGNL4

Alerts in IT, OT, IoT and Business Apps

Secure Connection and automated Delivery

Persistent Notifications with Tracking, Escalation and Confirmation to Staff on Duty

How SIGNL4 impacts Operations


If you have questions, check the FAQ below or ask our Bot through the online chat who has access to our online help.

Is there a free trial or demo?

Yes, you can try SIGNL4 any time for 30 days free of charge. Follow this link.

For demo videos, please visit Vimeo

Which notification channels are available?

SIGNL4 notifies via mobile push, text and voice call. One channel can be selected for persistent notification. The sequence of these comm channels can be configured freely.

How can I connect a 3rd party system?

The easiest way to connect your 3rd party system to SIGNL4 and to trigger mobile alerting flows is to send an email. Each team in SIGNL4 gets a dedicated email address. Send an email with any content to it and it gets translated into a mobile alert workflow.

The webhook can be used for connecting modern IT systems while the REST API provides for deeper integration and 3rd party control of functions in SIGNL4.

Please, find related information on integrations and the API here.

Who receives alert notifications (alert routing)?

All team members with the status ‘on duty’ receive alert notifications. This allows for managing timely availability of team members and automated routing to staff ‘on duty’.

Can I track if somebody acknowledges or handles an alert or work item?

Yes, absolutely. This is the fundamental principle of SIGNL4. When an alert/work item (signl) is submitted to staff on duty, they can acknowledge/confirm an alert or work item. This is done by hitting the encircled question mark section. If this person has set a profile image, it will be shown. If this section is tapped again, the alert/work item goes gray which indicates that it has been resolved.

The status of an alert or work item is visible throughout the entire team. Date and time of those action are tacked in the alerts audit train – the timeline.

Can multiple people confirm an alert?

Yes, this is the default mode of SIGNL4. All team members on duty are required to acknowledge an alert. You can change this behavior to a ‘first come, first confirm’ mode; in this case only one person on duty needs to confirm an alert. The later is often used in maintenance scenarios. You can change the alerting mode in the management portal of SIGNL4 (https://account.signl4.com/manage/).

Can alerts be escalated?

Yes. Alerts need to confirmed. If an alerts is not confirmed within a configurable ‘target response time’, it is automatically escalated to a ‘manager on duty’. Each team member can set his or her status to ‘manager’ by a double-tap on the profile picture on the app’s dashboard. You can watch a video here: https://vimeo.com/album/4858122/video/246436585 

How many users can my team have?

There is no limitation on how many users a team in SIGNL4 can have if you are on a commercial plan. The ‘forever free’ plan only allows for a maximum of five users per team.

Can I have multiple teams?

Yes. When you sign up, a single team will be created and you can add more teams any time. Teams are centrally managed and billed but their data like users and alerts are visible to them only.

If you want to be a member of multiple teams at once and with the same user account, you’ll need to wait until 2019.

How do these colorful alert categories work?

Under “Services and Systems” on the mobile app you can find configurable categories. To trigger a specific category, e.g. for an email alert, use one of the following options:

1. Define keywords in the respective Services&Systems category on the mobile app. SIGNL4 scans incoming content and uses a algorithm to find the best match.
2. Use ‘X-S4-Service:[categoryname]’ in the email body to force a category.

In case you are using the webhook API, use the JSON payload parameter ‘X-S4-Service’ : ‘[categoryname]’ to enforce a category. Here is a video: https://vimeo.com/album/4858122/video/244003265

What are the mobile device requirements?

You need an Android phone or iPhone to use SIGNL4. The minimum iOS version to run SIGNL4 is 9.0 . On Android devices the minimum OS version is 4.0.3 to run SIGNL4

How secure are my data?

SIGNL4 has been designed with highest security standards to protect your data. All data are protected by one of the strictest data privacy laws in the world. Service connectivity is secured via SSL (REST) and TLS (SMTP). Authentication of the mobile app is token-based and data are automatically erased from the mobile device if no valid authentication is provided.

How can I delete my account?

To delete your account, go to the SIGNL4 management portal (https://account.signl4.com/manage), log in and go to ‘Help’. Click ‘Terminate’ to cancel any existing subscription and delete your team and all data.

What is the availability of SIGNL4 (SLA)?

SIGNL4 uses Microsoft Service Fabric clustering technology to provide for uninterrupted service availability. Unlike other SaaS there is no single or redundant VM but an entire cluster. Since, mid Feb 2018 we operate a status page at http://status.signl4.com

Is there a user guide?

The mobile app is largely self-explaining. To speed things up a little, here is a video tutorial.

How can I trigger an alert from Windows Powershell?

Here is an example on triggering an alert through a Windows Powershell command:

Invoke-RestMethod ‘https://connect.signl4.com/webhook/‘ -Method POST -ContentType ‘application/json’ -Body ‘{“Alert”:”Error”,”Description”:”PowerShell alert.”}’

Note that you can add or use any parameter in the JSON payload.

Please note that is the 8 digit code that identifies your team and is uniquely created when you sign up. You’ll find it in the app under “APIs” or in the management portal.

How to trigger alerts from Unix/Linux via command line?

Here is an example on triggering an alert from a Unix or Linux command line:

curl -H “Content-Type: application/json” -X POST -d ‘{“Alert”: “Warning”, “Description”: “Linux backend server down.”}’ https://connect.signl4.com/webhook/

Please note that is the 8 digit code that identifies your team and is uniquely created when you sign up. You’ll find it in the app under “APIs” or in the management portal.

Can I trigger alerts from a web page?

Yes, sure. There is a built-in feature for sending alerts from the management portal.

SIGNL4 also provides a webhook API which can be used to trigger alerts from web site. Here are additional details: https://www.signl4.com/developers/webhook/inbound

You would use what we call the ‘inbound webhook’. It accepts various payload types to submit event/alert content.

If you have registered with SIGNL4, you can test-drive the webhook to trigger an alert here:

Where do I find the email address for triggering alerts to my team?

You find this dedicated team email address in the management portal (https://account.signl4.com/manage) or in the mobile app (Gear Symbol/Settings->APIs).

Can an email mailbox be queried?

Not yet. SIGNL4 cannot query an email mailbox (e.g. via POP3 or IMAP). Instead emails need to be routed to the email address each team gets in SIGNL4. You can for instance create a mailbox rule in your mail program to route all or specific emails to the SIGNL4 team email.

How can I trigger alerts from C# code?

Here is a great C# example from our inspirational blog.

What is my 'team secret'?

You can find your ‘team secret’ or ‘team id’ in two places. Either in the management portal on the dashboard (https://account.signl4.com/manage/) or in the app (tap the ‘gear’ symbol on the dashboard to go to settings, then tap APIs: the first 8 digits of your team’s email address are your secret).

How can I obtain an API key?

Currently, you need to request it manually. Please, send an email to account@signl4.com to request your API key.

And here is a blog post on how to work with the API key.

Get started

SIGNL4 on Google Play

SIGNL4 on Apple iTunes

Get started

SIGNL4 on Google Play

SIGNL4 on Apple iTunes