Most fax services assume you fax regularly: subscriptions, free trials that convert to $18/mo, desktop-first flows requiring PDFs. ProntoFax is built for the person who needs to send one fax to a court, the IRS, or an insurer — probably from their phone. Snap a pic of your pages , pay $2.99 flat, and you're only charged if the fax actually delivers. Fully bilingual English/Spanish end to end, because a huge share of one-off fax senders are Spanish-speaking and ignored by every incumbent.