**Related issue:** Resolves
https://github.com/fleetdm/fleet/issues/41968
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
- [x] Input data is properly validated, `SELECT *` is avoided, SQL
injection is prevented (using placeholders for values in statements), JS
inline code is prevented especially for url redirects, and untrusted
data interpolated into shell scripts/commands is validated against shell
metacharacters.
## Testing
- [x] Added/updated automated tests
- [ ] QA'd all new/changed functionality manually
## Database migrations
- [x] Checked schema for all modified table for columns that will
auto-update timestamps during migration.
- [x] Confirmed that updating the timestamps is acceptable, and will not
cause unwanted side effects.
- [x] Ensured the correct collation is explicitly set for character
columns (`COLLATE utf8mb4_unicode_ci`).
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Added support for using Fleet variables (`$FLEET_VAR_HOST_*`) in
Android configuration profiles, enabling per-host dynamic value
substitution during deployment.
* **Improvements**
* Strengthened Android profile validation to reject unsupported Fleet
variables and prevent invalid placements (for example, using variables
in JSON object keys or non-string fields).
* Enhanced deployment behavior when variables can’t be resolved for a
host, marking affected profiles as delivery failed and avoiding partial
policy application.
* Improved Android per-host rollout by applying installs in staggered
batches for smoother throughput.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Konstantin Sykulev
b32ceb72e1