Generally you should upgrade with the same service where you bought the initial subscription - Apple, Google Play or Billdu.
If you're not sure where you bought the subscription, take a look here.
Note: Subscribing with different services may result in double-charges if you don't cancel your previous subscription.
MOBILE APP
iOS (Apple App Store)
You can upgrade on an iPhone/iPad if you see a screen like this:
HOW IT WORKS
You'll be charged a full price for the new subscription and Apple sends you a refund. The amount depends on how long you've used the previous subscription.
Example
You've have bought an annual Light subscription in January. When you upgrade to Standard in June, Apple charges you for the selected subscription and refunds the amount of 6 month (January-June) of your Lite subscription - you'll get half of your Lite subscription back
Important information
Subscriptions bought before February 2019: Contact us if you're not sure about your Apple subscription and we'll assist you with an upgrade so you won't be charged the full amount.
Android (Google Play Store)
HOW IT WORKS
An upgrade activates the subscription for a period which corresponds to the prorated amount of your previous subscription.
Example
You've bought an annual Lite subscription in January and upgrade to Standard in June. Google Play looks up the prorated amount of the remaining 6 months of Lite (July-December), calculates the time-span accordingly and activates the Standard subscription for that period.
That means you get the Standard subscription for 2,5 months.
Important information
Please note that after this period the new annual Standard subscription activates for another full year.
BILLDU WEBSITE
HOW IT WORKS
If you've bought a subscription on our website or via our special promo link, you can upgrade on the Billdu website.
Navigate to Settings - Subscription and click on Upgrade.
Billdu displays the amount you'll be charged for an upgrade. It's a difference between your current subscription and the higher subscription.
Please note:
Your subscription is recurring. Next year you'll be charged the full amount for your subscription.