1) Wazzala.com is a free online preparation tool for English certification exams like TOEFL and IELTS that generates customized study guides for users based on their needs and tracks their preparation progress. 2) It provides skills maps that identify the skills tested on exams and their frequency, and ability maps that track users' performance on each skill and calculate their ability level. 3) Users take 4 practice tests during preparation that assess their skills in grammar, vocabulary, reading, and listening. Their performance is analyzed to further focus their studying.