HTC One Remix - Manual (Page 267)

Installing a digital certificate
Use client and Certificate Authority (CA) digital certificates to enable
HTC One remix to access VPN or secured Wi-FI networks, and also to
provide authentication to online secure servers. You can get a certificate
from your system administrator or download it from sites that require
authentication.
§ You must set a lock screen PIN or password before installing a
digital certificate.
§ Some apps such as your browser or email client let you install
certificates directly in the app. See the app's help for details.
1. Save the certificate file in the root folder on HTC One remix.
2. Go to Settings, and then tap Security.
3. Tap Install from storage.
4. If you have more than one certificate in the root folder, select the
certificate you want to install.
5. Enter a name for the certificate and tap OK.
Disabling an app
Apps, even if not used often, may be running in the background and
downloading data. If an app cannot be uninstalled, you can disable it.
1. Go to Settings, and then tap App manager.
Settings and security 267