Doppler Player app for iPhone and iPad

The Doppler Player is an audio player which can plays local audio files and Media & Apple Music audios (authorization required). It supports the following features:
1. The built-in 3D EQ can augment the sound reality while playing. It can add customized binaural sound effects to audio. It also provides 13 reverb presets (such as Chamber, Large Hall, Cathedral) and 22 distortion presets (such as Drums Bit Brush, Decimated, Echo). The user can change the settings while playing. For each 3D EQ presets, user is allowed to fine tune the effect by adjusting the delay, speed, etc. This feature applies only to local audio files without Digital Rights Management (DRM).
2. The built-in EQ provides 17 presets (such as Full Bass, Rock, Jazz, Classic, Vocal). Users can fine tune and save the EQ (5-band or 10-band) setting they like. Users can also choose the predefined and self-defined EQ settings while playing. For each EQ presets, user is allowed to fine tune the effect by adjusting bandwidth and gain. This feature applies only to local audio files without Digital Rights Management (DRM).
3. Users not only can enjoy the EQ and 3D EQ effects while playing, they also can export the audio files with built-in EQ and 3D EQ effects. After audio is exported, users can choose to save the audio files locally or share them with friends. When playing the exported audio file using this player, use may want to turn off the 3D EQ or EQ effect, otherwise it will be played with double effects.
4. When adding local audio files, users can choose to pick a folder and then add all audio files under this folder, or, pick a single audio file and add it.
5. To better arrange the audio files, users can create and delete playlists. The playlist here is different from the Apple Music playlist. This player also has a few built-in playlists such as "Favorite", "Recently Played Songs", "Exported Files".
6. To access the latest music resource, users can search and then play songs from Apple Music (account and network required.). Users can also search songs stored locally.
7. If user chooses to not allowing this player to access "Media & Apple Music", this player can only play local songs which the user choose to add.
8. There is no Ads when user uses this player to listen to music. However, there will be Ads when the user chooses to export audio files.