D4Sign API vs Dropbox Sign

D4Sign API has no write-up on Specifiction yet; its figures are above.

Dropbox Sign is an e-signature service for individuals and businesses managing online agreement workflows. It supports sending signature requests, tracking them, and sending reminders. Signatures are legally binding under the U.S. ESIGN Act of 2000, with the same legal standing as pen-and-paper signatures. Templates save prepared fields for documents sent repeatedly, and embedded signing lets signers complete the process within a website. The API uses OAuth 2.0 and has official SDKs for Python, Ruby, PHP, Java, NodeJS, and C#. It also offers an audit trail and identity verification; bulk sending is not available. Senders and signers can use 22 languages, with apps for iOS and Android as well as web and API access. Listed integrations include Google Workspace, Microsoft Word, Salesforce, HubSpot, Slack, and Zapier. Dropbox Sign states that it complies with SOC 2 Type II, ISO 27001, eIDAS, and GDPR, and encrypts documents at rest with AES 256-bit encryption. A free plan allows three signature requests per month. Paid plans start at $10.05 a month with annual billing, and a 30-day trial is listed.