Blockbook is described as '™ leverages Blockchain Technology, to provide you with Smart Contracts, Semi-Decentralized Cloud and a Manipulation/Tamper-Proof history and storage of your data and documents, via Blockchain Posting and Timestamping for FREE!' and is an app in the Bitcoin & Cryptocurrency category. There are three alternatives to Blockbook for a variety of platforms, including Online / Web-based, Windows, Android, iPhone and Linux. The best alternative is IBM Blockchain. Other great apps like Blockbook are ChainZilla.io (Paid, Open Source) and Oracle Blockchain Cloud Service (Paid).