MIFARE Classic Fallback Reader

While there are standard ways of MIFARE Classic operators identifying their cards (such as the MIFARE Application Directory), this is rarely used by operators and is not a requirement. Instead, these cards are typically identified by a standard string available at a fixed location on the card. This is sometimes called the "magic".

Not all operators contain such a "magic" string (or the "magic" is not yet known), so Metrodroid will have false positives reading some cards.

In Metrodroid 2.9.30, a new setting was introduced to mitigate this, called "Fallback reader".

If no other reader is able to detect the card type, the user-selected fallback option will be chosen instead. This is disabled by default (to eliminate false positives), and the user must opt-in and choose one reader to use as a fallback.

This is accessible in the preferences, under MIFARE Classic -> Fallback reader.

If a reader is chosen that is incorrect for the card, garbage information may be displayed, or the reader may crash.

As of 2.9.40 this setting is not required for any card