Although Amazon Fire tablets run the Android operating system, you can only download apps from the Amazon Appstore (it'd be way easier if they just let you access the Google Play Store!).
For this reason you won't be able to find Parent Hub in the Amazon Appstore but never fear, the guide below explains exactly how to get around this minor inconvenience!
On your Amazon Fire...
1. Open Settings > Security and then tap the switch to turn on "Apps from Unknown Sources".
(This setting is off by default and protects you against the accidental download of nasty apps. We're only recommending that you change this setting temporarily to enable the install of Parent Hub, after which you should turn it back off. See Step 7.)
2. Click here to download the Parent Hub app install file. Tap the Download button and then "Direct Download" to save it onto your Fire.
3. Once the download is complete open up your Docs app.
4. Select the Download folder and tap on the file named Parenthub-V2.1.4.apk (this is the Android app installation file).
5. Scroll down and tap Install.
6. Once the install is complete, you'll be able to find Parent Hub in your list of apps.
7. Once you've checked that the app is installed go back to Settings > Security and switch "Apps from Unknown Sources" back off.
If you have any questions about this or issues with the process, please do get in touch on firstname.lastname@example.org.