Types of software
Finance is complex and there are many use cases, from weekly allowance for children to managing multi-billion dollar retirement funds, to hectic day trading. So we end up with many different software solutions for the various uses cases. When designing, it's a good idea to have a feel for this landscape and know where your software fits. Here are a few common ones that are accessible by a general audience.
Blockchain explorers
If blockchain can be thought of as a public database, then explorers are simply windows into that database. They typically simply display the data structure as is and maybe offer some basic functionality like looking up specific transactions to verify that they were processed.
Command-line interfaces (CLI)
Primarily used by developers, command-line interfaces typically offer the most feature-rich options to interact with blockchains. However, they also require the most technical knowledge.
Graphical user interfaces (GUI)
Every project usually has one or more wallets that provide easy-to-use graphical interfaces for a wide audience to interact with the blockchain. Wallets many times don't offer all functionality that can be found in the CLI, but focus on general use cases like creating wallets and making payments.
For projects with strong open-source foundations, there are typically multiple options for software wallets available, since anybody can contribute. Bitcoin.org for example, offers 21 different wallets by different teams for download.
These wallets are the primary focus of this document. Read more about them here.
Multi-coin & digital asset wallets
As the blockchain space has exploded, thousands of cryptocurrencies and tokens have been created. Power-users may be overwhelmed with managing dozens of wallets - enter these new wallets for managing multiple currencies. While they simplify certain areas, they may not offer all functionality that each project provides and simply focus on making transactions.
Portfolio management apps
For investors and traders who frequently buy and sell coins, it's clearly important to track their portfolio and stay on top of price trends. Portfolio management apps typically do not allow for buying and selling, but focus on aggregating price data, display of graphs, and managing portfolios.
Exchanges
Exchanges are marketplaces for investors and traders to transact with each other. These interfaces are for power-users and filled with endless ways to view prices, order books and trading features.