In July, we announced that only videos with a 16:9 aspect ratio could be used with video app download cards. Starting today, video app download cards can be created using 1:1 videos. This provides advertisers with an additional option to test which video creatives work best with their MAP campaigns. Based on preliminary results, 1:1 videos are generating higher CTRs, on average.
Videos should be either .mp4 or .mov and cannot be longer than 140 seconds. (Note that some advertisers may have access to uploading longer videos.) We also suggest using 29.97 or 30 FPS videos with 6,000 - 10,000k bitrates for 1080p or 5,000 - 8,000k for 720p.
Recall that the GET accounts/:account_id/videos and GET accounts/:account_id/videos/:video_id endpoints include the
aspect_ratio response attribute so that developers can identify the videos that can be used in video app download cards.
Twitter Ads API Team