Besides iCloud or a sync cable, how can i back up my files?
If you plan on getting another iPhone

iCloud backs up everything on your iPhone—every game's data, every app's data, your health data, your messages, your phone logs, your settings, your Homekit data, your photos and videos, everything. If you get a new iPhone, when setting it up, you can choose to set it up from a backup, and that new phone will have all of the data your current phone has. The sync is as complete as backing it up to a Mac. Also—try the Google Photos (not Google Drive) app for awesome photo backups. 

If you need any help backing your phone up with iCloud or iTunes, check out Apple's support article.

Note: you can very easily get a new sync cable for your iPhone from Amazon. Here's a reliable one, and it's just $6.



If you plan on switching to Android or you're not sure what your next phone will be

Save your photos with Google Photos: download the app for iOS and it's really easy to back up all of your photos, and since Google Photos comes preinstalled on many Android phones (and is available from the Play Store on all others), your photos will be right there waiting for you.

Save contacts by going to iCloud.com and exporting them all as a VCard, then importing this into your Gmail contacts; see a guide here: https://support.apple.com/kb/PH3606?locale=en_US.

Notes synced to your Gmail account are just waiting out there in your google account, but notes synced to your iCloud account must be manually exported with Copy and Paste. Here's Apple's official guide on exporting your iCloud notes:


  To copy notes, open the Notes app at iCloud.com. Copy the text of each
  note and paste it into a document on your computer, such as a Pages or
  TextEdit document. Save the document to your computer. To export your
  notes as PDF, open the Notes app in OS X Mountain Lion or later.
  Select the note, then click File > Export as PDF and choose a
  location.


Emails are self-explanatory, just hook up the Gmail app on your next phone.

Calendars are pretty self-explanatory too, they should all be tied to accounts in the cloud you can sign in to on an Android phone.

Your phone number is hooked up to your Sim card, but be sure to deactivate iMessage if you switch to Android or you won't get some text messages! Here's a guide on that: http://www.imore.com/how-to-disable-deactivate-imessage-iphone-ipad

Anything else on your phone can likely be exported in its own way, and more than you may realize is tied to the cloud.