Push Notifications


Starting with v70, TwoToneDetect has built-in integration for Pushover and Pushbullet push notification services. This page will describe what push notification are and how they differ from SMS and MMS messages, and what the differences are between Pushover and Pushbullet so that you can determine which service is best for your situation if you want to send push notifications of fire calls to your members’ smartphones.

Push Notifications vs. SMS and MMS

Push notifications use a smartphone’s data connection to receive notifications from various sources.  If your phone receives notifications from applications like Facebook or Twitter, these are push notifications.  Your phone must be connected to a data network (either WiFi or cellular data like 3G, 4G, or LTE) in order to receive push notifications.

How are push notifications different from text messages (SMS messages)?  SMS messages use the cellular voice network to send short messages, so they can be received as long as you have voice cellular coverage, even if a data connection is unavailable.   However, SMS messages are text-only, so they can’t be used to send an audio file directly to a phone.  However, a hyperlink to a URL where an audio file is stored can be sent, and the user can then user their data connection to download the audio file.

MMS messages can be used to send audio attachments directly to a phone (even an older “flip phone” in most cases), but they require a cellular data connection.  Some phones will not download MMS messages via a WiFi data connection – cellular (3G, 4G, LTE) is required.

Push notifications can send text-based messages to a phone via data connection, and can contain a hyperlink to an audio file that has been stored on a server.  When the user clicks on the hyperlink the audio file is downloaded via the phone’s data connection and played.

One of the primary advantages of push notifications is that they don’t rely on the cellular provider’s SMS or MMS email gateway in order to send messages.  Therefore, the cellular provider’s spam gateways should not block any messages that are sent as push notifications.

The table below attempts to summarize the differences between using SMS, MMS, and push notifications to send alerts from TwoToneDetect.

MethodConnection RequiredAudio File TransferCellular Provider Spam Filter Impact
SMSCellular VoiceFile must be uploaded to web server and hyperlink sent in SMS bodyPotential Impact
MMSCellular DataSent directly to phonePotential Impact
Push NotificationData (cellular or WiFi)File must be uploaded to web server and hyperlink sent in push notificationNo Impact

Pushover and Pushbullet

If you want to send push notifications using TwoToneDetect, you can choose from Pushover or Pushbullet services.  TwoToneDetect is not affiliated with either of these service providers, and you would be responsible for setting up your own account and providing any payment necessary for use of the services (see below).  Here is a quick summary of the two services as they pertain to TwoToneDetect:

  • Free to send up to 7,500 messages per month
  • To receive push notifications, subscribers must purchase and install the Pushover app on their device (about $5)
  • To send audio files, TwoToneDetect must upload the files to a web server via FTP.  Pushover does not provide web server space to do this, you would need to use your own server.  TwoToneDetect.net can provide web server space with FTP access for a small monthly fee if needed.
  • Free to send up to 100 messages per month.  $3-$5 per month for unlimited messages
  • To receive notifications, subscribers must install the free Pushbullet app on their device.
  • Pushbullet provides web hosting space for audio attachments (up to 2 GB free) , and TwoToneDetect can upload them directly via Pushbullet’s API without needing to use FTP

While this site is not intended to be a step by step tutorial for setting up and using the Pushover or Pushbullet services, here are the general steps you would need to follow to use each of them to send messages with TwoToneDetect:

Pushover and TwoToneDetect

After you create your Pushover account you are able to create an Application/API Token and a Delivery Group Key.  TwoToneDetect uses these API tokens and keys to communicate with the Pushover server.  When you create an Application/API Token, Pushover will create a URL that you can send to your users that will allow them to subscribe to notifications from that Application using the Pushover app on their device.  You can set up a different Application/API token for each tone set in TwoToneDetect.

To set up TwoToneDetect to work with Pushover, you’ll use the following fields in the tones.cfg file (or in the TonesEditor GUI):

pushover_record_group_key =
pushover_record_app_token =
pushover_alert_group_key =
pushover_alert_app_token =

Put values in pushover_record_group_key and pushover_record_app_token to send Pushover notifications after audio recording has taken place.  These notifications will contain a hyperlink to the audio file that TwoToneDetect has uploaded to a web server via FTP.

Put values in pushover_alert_group_key and pushover_alert_app_token to send Pushover notifications as soon as an alert is detected but before audio recording has occurred.  These notifications will not have any links to the audio file.

You can use the same group key and app token for both the “record” and “alert” notifications if you want.  In that case all users who subscribe to that Pushover Application will get two notifications for each tone set that TwoToneDetect detects…one as soon as the tone is detected, and a second one after the audio is done recording.

Another option is to set up different Pushover Applications for the “record” and “alert” notifications and your users can decide which they want to subscribe to.

You can also leave the “record” or “alert” notification settings blank if you don’t want TwoToneDetect to generate Pushover alerts either before or after recording audio.

In order to have TwoToneDetect automatically upload mp3 files to a web server, the following fields in the config.cfg file (or the “Edit Config Info” menu on the main TwoToneDetect screen) are used:

upload_ftp_server =
upload_ftp_port =
upload_ftp_username =
upload_ftp_password =
upload_file_prefix =

The upload_file_prefix should be set to the web storage location where the audio files can be accessed via http.  For example: http://www.mywebsite/audiofiles/

TwoToneDetect will then append the file name of the audio file that was created and uploaded to the upload_file_prefix when creating the URL to send in the Pushover notification.

Pushbullet and TwoToneDetect

After you create your Pushbullet account you are able to create an Access Token.  TwoToneDetect uses this Access token to communicate with the Pushbullet server.  You can then create Channels over which you can send Pushbullet notifications to anyone subscribed to that Channel.  When you create a new Channel, Pushbullet will create a URL that you can send to your users that will allow them to subscribe to notifications from that Channel using the Pushbullet app on their device.  You can set up a different Channel for each tone set in TwoToneDetect.

To set up TwoToneDetect to work with Pushbullet, you’ll use the following fields in the tones.cfg file (or in the TonesEditor GUI):

pushbullet_api_key =
pushbullet_channel =
pushbullet_send_time =

The pushbullet_api_key will likely be the same for each tone set, unless you want to use multiple Pushbullet accounts within a single instance of TwoToneDetect for some reason.

The pushbullet_channel should be set to the name of the channel that you created for that particular tone set.  If you want, you can send multiple tone sets to the same channel.

pushbullet_send_time can be set to “before record”, “after record”, or “both”, and this dictates when TwoToneDetect will send notifications to the specified Pushbullet channel.  If “before record” is specified, a notification will be sent as soon as a tone set is detected, but it will not contain an audio file link.  If “after record” is specified, a notification will be sent after audio recording and uploading has been completed, and the notification will contain a hyperlink to the audio file that TwoToneDetect has uploaded to the Pushbullet servers.  Because Pushbullet provides server space and an API for uploading files, no additional FTP or web server is required.