According to the Techcrunch.com, the newly added button is present right next to the ‘Edit profile’ button, the account switcher and the Settings icon. By clicking on the Ads button, the users get the option of managing their Twitter ad campaigns while on the move.
It is uncertain at this time as to how many users are seeing the new Ads button since Twitter has not officially announced the addition. However, both the iOS and Android app were recently updated on their respective app stores.
Previously, the users could see the feature included in the list which appeared when they tapped the Settings option. At that time, Twitter Ads was visible right above the options for Lists, Drafts, and Help.