maara wrote:
Thanks for your explanation!
Are these codes related to any of the two slots? - would reprogramming some of the slots (I am using OTP and OATH in slots 1 and 2) cause that the codes will be deleted?
They are not related to the two slots (usually). Yubico Authenticator generally uses the smart-card chip in the Neo, not the Yubico chip, and stores the OATH credentials away from the two older-style slot areas.
Recent versions of yubico authenticator (at least on the desktop) have added support for setting/reading the older slot-based storage of up to two HOTP/TOTP OATH credentials (named Slot 1 and Slot 2, I think). If you have been using a NEO with Yubico Authenticator to set up the credentials without setting any non-standard slot-based options, there should be no impact when configuring the slots using yubico's other tools.
maara wrote:
How to ensure that these codes are safe and will be not touched in any other way than from the OATH app in the phone?
Set a password in Yubico Authenticator.
Brendan