Prerequisites

Confirm each of these before you start the Getting started flow.

Hardware

• An Android device with USB-host (OTG) support, minSdk 24 or newer.
• A USB-OTG adapter (or a powered OTG hub — some optical sensors draw more than a phone port supplies).
• A supported USB fingerprint reader (see the device support matrix):
  • SecuGen — FDx SDK Pro readers, including the U20 optical sensor.
  • Suprema BioMini — BioMini family.
  • EADAK / Aratek TrustFinger.

Credentials

You authenticate as the integrator, not the end user. Slade ID issues you either:

• a client id / client secret (OAuth2 client_credentials) — the SDK mints and refreshes the bearer on-device via ClientCredentialsAuth, or
• your own bearer token supplied through an AuthConfig callback.

Authentication is needed for every operation.

Build toolchain

• JDK 17+.
• Android Gradle Plugin 8.x, Gradle 8.5+, Kotlin 1.9+.
• Kotlin coroutines on the classpath (the SDK’s public surface is suspend + Flow).

App configuration

• android.hardware.usb.host feature declared, with a device_filter; on some device builds also a manifest <receiver> for USB_DEVICE_ATTACHED — see Device discovery.
• Consumer ProGuard rules are shipped with the AAR; if you obfuscate, keep the public API, JNI methods, and vendor classes (org.opencv.**, vendor SDK packages).