backpacking japan to india one year

I cannot answer your technology questions, though I suspect become an expert on smart phone is the most common solution.

You seem to be combining "both types" of back packing, hosteling and actual camping.

Parachuting and diving are each expensive events although you can snorkel for pretty cheap and see everything you would whilst diving.

As for the camping part of your backpacking I am a boy scout leader and of the many pages I could write about that, the most important points are
- always camp near water
- bring a ground pad in addition to a sleeping bag
- have a back-up plan in case you get sick or injured.

Good luck on your journey.

I would recommend you to by a small netbook. In South East asia (cambodja, thailand, laos, Vietnam) a lot of hostels - if not all - have wifi. So really easy to Skype with family/friends, post travel stories on the blog, upload photo's.
I used my netbook to type travell stories and also have a back up of our pics. We also bought a small external hard disk. Cheap and really easy.

Dont know what you plan to do in other countries like japan, india but cambodja, thailand, laos, Vietnam,... are so cheap to sleep that it doesnt make sence to bring a tent. They dont even have campsites.

My husband and i have been to south east asia in 2011-2012 and travelled more or less slow. meaning 6 weeks laos, 5 weeks cambodja, We have spend 35 to 38 euros a day, for 2 people.
Our advice: the slower you travel the less money you will spend.

If you stick around at an Island to dive, you can also lower the costs of the diving trip if you allow yourself time to just lay back and read books for couple of days in order to reduce costs.
Dont know if that makes any sence to you - but you cannot do crazy stuff every day and in the end no matter how much time you have you will Always have to make some decisions/choices

good luck with planning, you will be fine

Netbook would be better to upload pictures and videos. Depending on what format you are shooting in, you'll spend hours and hours at internet cafes trying to upload stuff.

I'm pretty sure most people on this forum have done a year with a backpack, and the advice you'll get goes along the lines of: stay as flexible as possible. Research the basics, e.g. visas, rough idea of budget (Use the forum 'search' function for this), flights. Sit down at a bookstore coffee shop with some Lonely Planets and get ideas.