Bitcoin + Lightning Wallet

An Android phone app

Essential app guide

An info you need to know before you start using a Lightning Wallet
Setting up a Bitcoin wallet
Using Lightning wallet

When something goes wrong

What to do when you no longer have an access to your wallet
Recovering lost Bitcoin balance
Reimbursing funds locked in a lost payment channel

Info on Olympus server

A helper service for Lightning stuff
What does Olympus server do
Storage tokens

Setting up a Bitcoin wallet

Upon opening the app for the first time you will be prompted to create a new Bitcoin wallet which alows you to send and receive regular Bitcoin transactions. Wallet data is always stored and encrypted on your device so you will have to use a password of your choice to keep your wallet secure.

Every new Bitcoin wallet is generated randomly, so it’s not tied to your device in any specific way. This is particularly important as it means that simply reinstalling the app and creating another Bitcoin wallet won’t restore your previous balance - you will get a completely new wallet instead!

There is, however, a simple way to preserve your balance across app reinstalls and even across different devices: you need to write down a mnemonic code once Bitcoin wallet is created.

Mnemonic code

Keeping your mnemonic code secure is very important. It is essentially a secret phrase comprising of 12 random words which is automatically generated by the application when a new wallet is created. Please remember: whoever knows your mnemonic code also fully controls your bitcoin so it should be kept private and secure at all times.

Also, only the mnemonic code can get your balance back in case you lose your device, forget your wallet passcode or simply uninstall the app by accident, it’s that important! One of the following actions should be taken once a new wallet is created to protect you from losing your balance:


In general there are two different pieces of private data associated with your wallet: the mnemonic code and your wallet passcode.

Your passcode is required to send coins from within the app and the mnemonic code is the only way to restore your balance in emergency situations such as lost/stolen device, forgotten passcode, uninstalled app etc.

How balances are displayed

Bitcoin is only allowed to be spent if the incoming transactions have been confirmed and as such it displays a balance in a way which may seem strange at first. Let’s imagine the wallet is empty and you have an incoming 1 BTC transaction. Here is how your balance will be displayed:

  1. While the 1 BTC transaction is unconfirmed: 0 BTC + 1
  2. Once the 1 BTC transaction gets a confirmation: 1 BTC

Now let’s imagine you’ve decided to spend 0.1 BTC, here’s how a balance will be looking:

  1. While the 0.1 BTC transaction is unconfirmed: 0 BTC + 0.9
  2. Once the 0.1 BTC transaction gets a confirmation: 0.9 BTC

Consider a real-world example in order to understand this: you buy a snack costing $1 but you only have a single $10 bill. At the start you have $10 viewed from every possible angle. After you order the snack you hand over your $10 bill. From the perspective of your wallet you have zero dollars now, but you know in a few seconds the shopkeeper will give you back $9 in change.

This situation is very similar in Bitcoin where an unconfirmed transaction may be viewed as a period of time between you handing over your $10 bill and getting $9 back.

Next: Using Lightning wallet