NOTE : Shared links don’t render HTML content in a web browser
Refer https://www.dropbox.com/help/desktop-web/force-download
Check question
How to force render a file in a browser
EDIT : Reason is you will need to change link url and reupload it :
- replace
www.dropbox.com with dl.dropboxusercontent.com inall links
Reupload by making changes in link which are in html and plist file again.
Thats it. Enjoy
TOTAL SOLUTION
Needed file for distribution using example link are given below :
- Build your app from xcode using Build and Archive option.
Upload your ipa file to Dropbox. And get public link for the ipa.
Note : replace www.dropbox.com with dl.dropboxusercontent.com in the link.
Download the manifest.plist - edit the line #14 with the public link of your ipa . Modify other keys as well (bundle-identifier, bundle-version, title) .
Upload the modified manifest.plist to Dropbox and get its public link.
Download the index.html - edit url param at line #8 with public link of your manifest.plist
Hosting using Github. How that can be achieved is explained in following steps
- Create a new project.
- Add index.html as we will be hosting a site in Github Pages. Note
html file with other name will not be valid as it should always be
with index name.
- Now go to project settings. Traverse through Github Pages
- Under source tab select master-branch and click on save
- Traverse back Github Pages you will see site will be published

Now you have Download link like https://paresh-navadiya.github.io/install.html/
Refer How to distribute using DropBox by @
oldman's answer and Distribute your iPhone/iPad adhoc builds Over The Air using DropBox
It working 100% percent.
Have a nice day to all :)