When interviewing, correct pronunciation is essential for being understood. It’s also crucial for putting an interviewer at ease. A heavy accent will not necessarily prevent one from landing a job, but it’s hard to think of situations when it would help.
Cambridge English Online has a brilliant, if a bit dry, app to help English learners practice their basic phonemes. The program has 19 activities and resources, including record and playback. It’s called by Mobile ESL the best mobile ESL app on the market.