You can download and use all four apps for free.
  

If you choose additional purchases, 

When using the Tems app, you can use the pro version for USD 1.99 per month (USD 19.99 per year). 

Pro version : Access to unlimited categories and record items

The four apps have a common starting point of 'item recording', but are services with different functions. 

• Listbook is recommended for those who want to share and expand their tastes by recording products and places. Additionally, you can share, exchange, or sell your belongings to someone who needs it more. 
• Tems has the advantage of digitizing the items you own and managing them at a glance. You can also analyze item usage patterns through the timer and history functions within the Tems app. It is good for people who pursue minimalism, buy the same items repeatedly, or have a lot of neglected items. 
• Flashmob is an event app where you capture and share your own items based on a different topic given everyday. 
• Listbook Archive is good for people who want to see item information from actual users and information provided by brands in one place. 

To use the Tems Pro version, you can pay within the app. 

You can request a refund through ‘App Store -> Account -> Purchase History.’