The need for a custom solution
It should be noted that you should not pay for a Fire without ads as these will be disabled in the "Locking down the tablet" section. Viable and cheaper alternatives to a brand new HD 10 would be a refurbished HD 10 for $120, a new HD 8 for $80, or a refurbished HD 8 for $70. I got the HD 10's used in this project for $95 each during the 2019 Prime Day sale.
Install the Play Store on your Kindle Fire
Following this tutorial, change your security settings to allow apps from unknown sources and download and install Google Account Manager, Google Services Framework, Google Play Services, and Google Play Store. At this point, the vastly superior Google Play Store should be installed as an app at the bottom of the Home screen.
Using the Play Store, download Settings Database Editor, and Fotoo. Using a browser, download and install the Fully Kiosk Browser for Fire OS APK.
Easy upload/display: Google Drive and Fotoo
Create a throwaway Google account that you will use on the tablet if you intend to give the photo frame away to friends or family. Using this account, go to Google Drive and create a new folder, call it "Shared Pictures" and share it with your own Google account and any other accounts you may want to have "display" privileges on your distributed photo frames (in the folder, click on the folder title and select "Share+"). You will now have a "Shared Pictures" folder in your own Google Drive under "Shared with me." To upload pictures to this folder, simply drag and drop images from your computer. Go ahead and load a few test pictures here. If multiple displays are being distributed to multiple people with different interests, go ahead and create sub-folders that will be user-specific or shared.
For displaying pictures there are a myriad of viable options; I used Fotoo.
Open Fotoo and connect it to your Google Drive, selecting the "Shared Pictures" folders (alternatively, the sub-folders of interest). You now have a workable photo frame! But we aren't done yet, tap your tablet to pause the photo stream and select settings. Change Display Time to your preferred time, change Display Effect to Scale to Fit Center if you'd like "normal" picture display, change Transition Effect to Fade, change Photo Order to Modified First. Under Others, select Keep Screen On to prevent the tablet from going to sleep while showing images, and change Screen Rotation to Landscape. Finally, increase the Disk Cache Limit to 12,000 MB (12 GB) to save more of the pictures locally and make your photo frame less dependent on WiFi uptime.
Back the main landing page, hit "Go Premium," otherwise the slideshow will stop about once an hour for five minutes. If you are distributing the display to multiple users, make sure you are using the same Google account on the Play Store as purchasing Fotoo Premium on one device will work for all linked devices.
Locking down the tablet
- Douglas Adams
I want to make this photo frame as easy to use as possible, and by that I mean I want to lock this tablet down. Create a folder by clicking and holding one app and hovering it over another and releasing. Pile all apps other than Settings, Fotoo, SetEdit, and Fully Kiosk Browser into this folder.
Open Settings and navigate to Display -> Screen Sleep and change to 30 min which will allow people to pass around the tablet while unplugged without going to sleep. Go back to the first settings page and navigate to Apps & Notifications -> and turn Notifications Off.
To remove the lock screen entirely (which is why you should not pay to remove ads, this step removes them automatically) we follow the guide by computerhilfren.
Go to Settings on the Home screen and connect the tablet to your PC. To enable developer options select Device Options -> About and tap the Serial Number seven times (seriously). Select Developer Options and change Stay Awake to On so the tablet does not sleep while charging, and turn USB Debugging (might appear as Enable ADB) On so you can communicate with the tablet from your PC.
On your PC, download the Android SDK Platform Tools and unzip. Place the platform-tools folder in C:\ and open the command prompt. Type "cd C:\platform-tools", enter. Type "adb devices", enter. On the Fire, select to allow communication on the pop up. Repeat "adb devices" to confirm the existence of a connected device. Type "adb shell pm grant by4a.setedit22 android.permission.WRITE_SECURE_SETTINGS", enter. You can now unplug the Fire.
Going back to the tablet, open Settings Database Editor which will appear as SetEdit. Select "Secure Table" in the top right and change "lockscreen.disabled" to 1. Select "Global Table" in the top right and change "device_provisioned" to 0. This second step does some funky things to your tablet settings menu and seems to disable app downloads from the Play Store, so if you find you are missing options in your settings that you would like to access or other apps you would like to install, change "device_provisioned" back to 1 temporarily.
Restart your tablet to confirm that the Fire will boot with no lock screen. Open Fully Kiosk and go to Settings, Kiosk Mode (PLUS). Enable Kiosk Mode and select Single App Mode, choosing Fotoo from the app list. This allows Fully Kiosk to keep Fotoo running at the front of the device.When exiting Fully Kiosk, select Yes to turn Kiosk Mode on. Fotoo should boot immediately to the main landing page. Ideally, the slideshow should be set using the lock button at the bottom of the landing page, which just requires one extra step to get back to the main menu.
To break out of Kiosk Mode, tap the screen seven times very quickly and enter the PIN (unless you have a good reason, I would recommend simply keeping the PIN as default 1234). Back in Fully Kiosk, select Exit Kiosk from the left.