The Pearson Test of English Academic (PTE Academic) has similar test sections of Reading, Listening, Speaking and Writing in 2 versions of Academic and General training like in the IELTS. However, there are several distinctive features in the PTE Academic exam format which makes it stand apart from IELTS.
In IELTS, the examiner evaluates the speaking abilities of the candidates by making live online conversation whereas in PTE, there is no live conversation and the candidate has to speak to a computerized system for recording which is then evaluated by a computer program to rate the test taker. However, PTE is entirely computer based and therefore uses many creative techniques to test the writing capabilities of the candidate, unlike the IELTS that uses a paper-based format for the conduct of the test.
IELTS has a specific time for each paper, and test takers can move across section and can attempt any question, whereas PTE has set a stipulated time for each module and has to only follow the chronology to complete the test.