A Lot Of Blogger’s Who Use Free Blogging Platform Prefer Blogger, Knowing That Most Blogger’s Use Mobile Devices To Visit The Web I Decided To Write This Article On How To Upload Template With Your Phone. 
Although I Don’t Know If It Works On All Mobile Devices But It Has Been Tested With UCbrowser On S60 Phones And Worked Perfectely.
1. Go To Your Blogger Dashboard
2. Click On The Blog You Want To Upload The Template To
3. Now Click On Templates as In The Photo Below 
4. Click On BackUp / Restore 
5. This Is A Little Trick You Will Have To Apply To Get It All Done. Scroll down A Bit, You Will See An Upload Form, Select The Template You want to Upload. If you click on Upload, It Wont Work.
Now, you will Click on The Settings Button as In The Photo Below:
6. Wait Till The Page Loads. And Dont Exit the Page Yet… Scroll down to the Bottom Of The Page Where You Will Find Another Upload Form.
Now, Select Your Template, Click On The Upload Button as Below, Wait For It To Finish Upload.
Now Preview Your Blog and See How It Looks.
If You Encounter any problems During This Process, Dont Forget To Inform Us via the Comment Box..