Tuesday, August 28th 2012

How to upload photos from a Canon/Nikon DSLR to an Android phone

I have been trying for quite some time to connect my Canon EOS 7D to my Samsung Galaxy SII (or GT-I9100 if you like), in order to import/copy photos and upload them to Facebook, Twitter, etc. Only the other day did I actually succeed.

There didn’t seem to be much information on how to do this, so I thought I would make a simple guide here.

While I’m using a Canon EOS 7D, this should work the same if you have a T2i/550D, T3i/600D, T4i/650D, 5D, 5D mark II or III, 50D, 60D, or whatever Canon DSLR it may be. (Edit: I have also found an identical solution for Nikon users, even if I haven’t tried it myself.)

Most importantly, your phone needs to support USB on-the-go. Sadly, not all Android phones do, but if it is in this list it should be fine.

Step one: The USB connection

To connect your phone you need a USB on-the-go (OTG) cable as well as the USB cable that came with your camera.

I believe a USB OTG cable is the same thing as a USB host cable – correct me if I’m wrong. It is essentially a cable with a USB micro connector at one end (which goes in your phone) and a standard size USB socket at the other (where you plug in your camera’s USB cable). For the record, mine is a third party cable that I got from Kjell & Company (a Swedish gadget chain).

USB on-the-go connector

When you connect your camera (make sure it’s on!) to your phone, a little USB symbol should show up at the top of the screen:

Screenshot Android USB connector connected

Step two: The app

I read somewhere that the default Android Gallery app could be used to browse and copy jpegs from a connected camera, but I never got that to work. I almost gave up in fact, but yesterday I had another go and found the answer.

I give you: The CR2-Thumbnailer app. (If you have a Nikon DSLR, see the NEF-Thumbnailer.)

CR2-Thumbnailer app on Google Play

The app costs something like $4 (27,50 SEK), so before you buy it you should try the demo version to check that it works as it should with your combination of phone and camera. (Nikon users: Demo version here.)

This app goes even further than just copying jpeg files from the camera. If you shoot raw, CR2-Thumbnailer can extract the jpeg image that is embedded inside the raw file. That way you don’t have to switch to raw+jpeg when you want to upload a photo with your mobile. Fantastic!

Apart from extracting jpeg files, the app can backup your raw files to the phone’s internal memory or any memory card you have in the phone.

When you connect your camera after installing the app, it should detect the camera and start up automatically:

screenshot CR2-Thumbnailer

Press the blue camera and navigate down to the folder containing all your images. In my case it is 7D/CF/DCIM/100EOS7D/.

This is the thumbnail view you should find:

screenshot CR2-Thumbnailer thumbnail view

If you tap an image, it will open in fullscreen. Tap it again and you will see some buttons at the bottom of the screen:

screenshot CR2-Thumbnailer fullscreen view

The button next to the save icon lets you share your image straight from inside the app. (For some reason though, Twitter doesn’t appear in the list of available sharing apps.)

If you tap the i symbol, the app will show you the Exif info of your photo:

screenshot CR2-Thumbnailer exif info view

If you choose to save an image, you can choose which size you want to export: (You might need to enable this in the preferences first.)

screenshot CR2-Thumbnailer jpeg size

In the thumbnail view you can toggle between two different modes, using the button at the top right hand corner. The second mode allows you to select several images at once to be saved as jpegs or raw files to your phone:

screenshot CR2-Thumbnailer multiselect mode

After selecting a few photos, tap the menu button to get the following options:

screenshot CR2-Thumbnailer multiselect options

In this case, Save means extracting the jpeg and saving it to the phone. Backup will instead copy the whole raw file to the phone.

Thankfully you can choose to automatically save or backup to a specific folder, so you won’t get nagged for each and every photo.


Ever since I bought my Samsung Galaxy SII I have been wanting to use it for quick and on-the-go uploading of photos from my real camera. 🙂 Now I have finally found the app that will let me do so.

CR2-Thumbnailer will be very handy when traveling. I have a 32 GB memory card in my phone, so I can leave the laptop at home and just use my phone to backup all the photos and share the odd one on Facebook if I like.

There are still some things that can be improved though. It would be great if the app could remember the last folder I viewed, as well as allow me to sort the photos from newest to oldest – that would save me a lot of scrolling.

On the whole though this setup works very well!

28 Responses to this post:

  1. Feri Frastiansyah says:

    Great post…!! I Love it. Could I still continue shooting while it connected with the USB on-the-go through device? would it transfer my images immediately after I release shutter? or it just connect and copy stuff from my camera.

    your answer would help me so much 🙂

    *Sorry for bad English.

  2. David Naylor says:


    I’m not sure if you can keep shooting when connected, I haven’t tried. Perhaps you should have a look at the Android app “DSLR controller”?

  3. Scott Simmons says:

    Thanks I have been trying to figure this one out. I’m going to try and female USB to Female USB and see if that will work instead of buying a special cord.

  4. David Naylor says:

    Yes, that could well work. Let us know!

  5. Ashley says:

    Thanks for the instruction. I had been looking for an inexpensive DSLR with an Instagram app for convenience. Now I found an alternative process that will work just as well! Thank you so much

  6. Doug says:

    Desperate to get this to work with Galaxy Tablet 2. Very frustrating. Any ideas.Would be much appreciated

  7. euphoria says:

    Do my image frame need to size down and must my image be in raw format? I usually used to copy them on my desktop then I copy them on my phone and the picture turns out blurry… Why is that so?

  8. madey says:

    thanks…very good instruction..1 thing i dont understand, how do i connect
    usb cable to android – camera…can u show me how u do that..

  9. JPalmer says:

    What is you experience using video with this app and your camera.
    I have Nikon D-200 and a Galaxy III
    Thanks for you site most interesting…and seems to open new doors.

  10. David Naylor says:

    Sorry, I haven’t tried moving video across the USB connection but I imagine it should work in some way or another.

  11. Lasse says:

    Perfect, thanks 🙂

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  13. Ryan says:

    So, can you set it up so it is immediately uploaded into a cloud service like Google Drive or Dropbox?

  14. Mary Ellen says:

    This is so helpful. I have an older Canon PowerShot A95 and with the OTG cable I can attach to my Sony Xperia Z Tablet for download. I tried the demo and it recognized the camera and I could see the photo images. Not sure how limited the demo is as it seemed to save photos but I could not locate them in any folder and when I did the connect to FB the photo did not go. Any help with that? Ready to buy the full version but if I can not save (and find photos) or send to FB then it won’t do what I’m looking for. Thanks.

  15. P-O Sjoberg says:

    Great! Been lacking this solution when stumbling across bears and eagles, but it finally came in handy on the last beaver cam shooting.

  16. David Naylor says:

    Mary Ellen: Are you using the Gallery app to find your photos? It can be slow to update its thumbnails, try the app ES File Explorer instead.

  17. David Naylor says:

    P-O: Kul att höra! (I take it you’re Swedish.)

  18. Jaap says:

    It does not work on my galaxy tab 2. Any ideas?

  19. Razif says:

    I bit confuse with the connection from phone to Canon 7D. I use the USB OTG cable from my SIII than I use the Canon USB cable from camera BUT how do I connect this 2 cables. Now I had 2 same standard size USB socket..??? Do I need to purchase an adapter???

  20. Ignacio says:

    Thank you for so usefull information.
    Has anyone connected a Canon 400D to a Galaxy Note 8 using CR2 thumbnail?.
    Thanks in advance for your answers.

  21. nugie says:

    It’s really a great and useful piece of info. I’m glad that you just shared this useful info with us.Please stay us up to date like this. Thank you for sharing.

  22. Thanks a bunch for this very clear article! I’m a Nikon and S4 user and found the way to connect these oh so important gadgets together 🙂

    Btw, I finally got the Nikon pictures to show on the Android Gallery when connected, but not sure how I got there! It wouldn’t work, then I removed the SD card from my S4 and re-inserted it. Maybe that forced the S4 to re-read all pictures galleries, and got it to dosplay the Nikon pictures as well (both cards in my Nikon D7000 show up in the Gallery!)…

    Cheers, Greg

  23. Ivan says:

    Thanks for the article… I have a GN2 which should support USB OTG, and it works on external HDD but not the CF card in 7D. The phone shows USB connected but doesn’t detect the camera nor the card. Anyone has similar experience, and any solution for it?

  24. John K says:

    Been trying the app with my 30D. Motorola Defy XT, Sony Xperia Z tablet, and a. Samsung Galaxy SII. None seem to work. Anyone have success with a Canon 30D??
    Many thanks,
    John K

  25. Jason says:

    Trying to use this for a Canon G15 and Samsung S4 and the S4 does not recognize the Canon….I have a 16 G add-in card in the S4. Any thoughts?

  26. David B says:

    Thank you so much for this really useful instruction I was beginning to think that I wouldnt be able to upload my photos to my Hanspree tablet but now I can. Thanks very much for sharing this information
    Best Regards
    David B