Beginning with version 4.08, the Zello Android app will support screenless network radios like the Inrico T199 shown below. TYT W700 network radios can also be configured using the same steps as the Inrico T199.  

To set up and configure Zello for the Inrico T199 follow these steps.

Installing the Zello app and configuring an account

Since the device doesn't have a screen, you'll need to use a computer to configure it.

1. Download an Android remote control application to your computer. For example, Vysor is one such app that works on both Mac and Windows PCs. NOTE: Zello is not affiliated with, or endorsing, Vysor
2. Connect the Inrico T199 to your computer using a USB cable 
3. Use Vysor to configure the device and install Zello from Google Play or the Zello website.  

Creating channels and contacts for the selector knob

For the free app, use steps in the Android User's Guide to add the channels and contacts that you will map to the selector knob. Up to 16 channels and contacts combined can be mapped. It's helpful to name your channels and contacts by adding a two-digit numercial prefix indicating it's position on the knob before you begin mapping to the radio. As an example, "01 Station HQ" would be the first knob selection, while "02 EMS" would be the second knob selection. You will need to use these names during the mapping task below.

If mapping to ZelloWork channels and contacts, note that those display names are created and managed centrally in the ZelloWork Admin Management Console. The Admin for your network should use the Management Console to create channels and contact usernames with the same two-digit prefix naming convention as the free app.

Mapping the push-to-talk button and secondary buttons

1. In the Zello app, go to Menu>Options>Push-to-talk buttons
2. Click the "+" icon, then press the PTT button on the side of the device. The Zello PTT button will be added to the list
3. Repeat for additional buttons
4. For each button added to the list, you can edit button details and select a specific channel or contact to key up with when the button is pressed. This is especially useful for secondary buttons. For example, you can have secondary buttons mapped to an emergency channel or contact so they are always accessible.

Mapping Zello channels and contacts to the Inrico channel knob

The Inrico T199 radio includes a knob that allows you to switch through channels. To map Zello channels to channel numbers on the T199, do the following from the Zello app:

1. Select Channels and then click on the channel that you want to map. The talk screen for this channel will display. If your channel already has a two-digit prefix in its name to indicator knob position, skip to step 4. Otherwise, continue with steps 2 and 3 
2. From the talk screen, click on the arrow down icon, then select Rename channel
3. Change the channel name, mapping it to the appropriate knob position. For example, if you have a channel named "CB Friends", rename it to "13 CB Friends" so it will be mapped to knob position 13. For channels with numbers under 10 use a leading zero (i.e. "01", "02" etc). You can map up to 16 channels and contacts combined.
4. Exit the channel talk screen and then rotate the knob to test your changes. When the channel is selected, its name will be announced using text-to-speech. The channels are switched in their numerical order. For example if you have channels 01, 07 and 13 assigned, rotating the knob will make channels switch in the following order: 01 -> 07 -> 13 -> 01 -> 07, etc.
5. Repeat steps 1-4 for all of the channels and contacts that you need to map. However, for contacts, instead of selecting Channels in step 1, you would select Contacts and then select and rename the contacts you want to map. Be careful to use unique prefixes for different channels and contacts.