Image-selection CAPTCHAs (select all images with X)
Audio CAPTCHAs
Invisible or behavioral CAPTCHAs
Websites like Google, Facebook, and Reddit use behavioral analysis to detect bots. If your Android device solves CAPTCHAs too quickly (e.g., 0.5 seconds vs. the average human 8 seconds), their firewall will flag you. Repeated use can lead to:
Automating CAPTCHA solving to bypass rate limits or access restricted data can lead to: auto captcha solver android
Many “free auto captcha solver” apps on third-party app stores contain: Image-selection CAPTCHAs (select all images with X)
Tesseract is the go-to open-source OCR. On Android, use tess-two (a Tesseract fork for Android). Audio CAPTCHAs
Setup:
val tess = TessBaseAPI()
tess.init(DATAPATH, "eng") // DATAPATH points to tessdata folder
tess.setImage(captchaBitmap)
val text = tess.utF8Text
But raw OCR fails on distorted text (noise, lines, rotations). So we preprocess.