KingSumo
KingSumo is a viral giveaway platform that helps you grow your email list and social media following through incentivized sharing and automated contest management.
Email on Acid
Email on Acid is a comprehensive email pre-deployment platform providing automated testing, content checking, and deliverability tools to ensure your campaigns look perfect across all major inbox providers.
Quick Comparison
| Feature | KingSumo | Email on Acid |
|---|---|---|
| Website | kingsumo.com | sinch.com |
| Pricing Model | Freemium | Subscription |
| Starting Price | Free | $74/month |
| FREE Trial | ✘ No free trial | ✓ 7 days free trial |
| Free Plan | ✓ Has free plan | ✘ No free plan |
| Product Demo | ✘ No product demo | ✓ Request demo here |
| Deployment | ||
| Integrations | ||
| Target Users | ||
| Target Industries | ||
| Customer Count | 0 | 0 |
| Founded Year | 2011 | 2009 |
| Headquarters | Austin, USA | San Antonio, USA |
Overview
KingSumo
KingSumo helps you turn strangers into subscribers by running viral giveaways that people actually want to share. Instead of paying for expensive ads, you can offer a prize and let your entrants do the marketing for you. The platform uses a unique referral system where users earn extra entries for following your social profiles or inviting their friends to join the contest.
You can set up a professional giveaway page in minutes without any coding or design skills. It handles the heavy lifting by tracking referrals, verifying social media actions, and automatically picking winners. Whether you are a blogger, podcaster, or e-commerce store owner, you can use these contests to build a massive, engaged audience quickly and affordably.
Email on Acid
Email on Acid helps you eliminate the guesswork of email marketing by previewing your campaigns across over 100 different email clients and devices. You can catch rendering issues, broken links, and accessibility problems before you hit send, ensuring every subscriber has a consistent experience. The platform automates the tedious manual testing process, allowing your team to deploy high-quality emails faster and with more confidence.
Beyond simple previews, you can optimize your inbox placement with deliverability tools that check your IP against blacklists and validate your SPF and DKIM records. Whether you are a solo developer or part of a large enterprise marketing team, the platform provides the technical insights needed to bypass spam filters and improve engagement. You can integrate these checks directly into your existing workflow to maintain brand standards across every communication.
Overview
KingSumo Features
- Viral Referral Tracking Give your entrants extra chances to win when they share your giveaway with their friends and family.
- Social Media Integration Grow your following by rewarding users with bonus entries for visiting your Instagram, YouTube, or Twitter profiles.
- Automated Winner Selection Save time and ensure fairness by letting the system randomly select and verify your giveaway winners automatically.
- Custom Landing Pages Create high-converting giveaway pages with your own images, descriptions, and branding in just a few clicks.
- Email Service Integrations Sync your new leads directly to popular platforms like Mailchimp, ConvertKit, and Zapier for immediate follow-up.
- Embeddable Widgets Place your giveaway directly on your own website or blog to capture visitors where they already are.
Email on Acid Features
- Unlimited Email Previews. View your email exactly as it appears on 100+ combinations of devices and clients to ensure perfect rendering every time.
- Campaign Precheck. Run an automated checklist to verify links, images, and accessibility standards so you never miss a critical error.
- Spam Testing. Test your emails against 23 different spam filters to identify potential delivery issues before they impact your open rates.
- Email Editor. Make real-time code changes in a live editor and see instant updates across all previews without re-uploading your files.
- Accessibility Checks. Optimize your emails for screen readers and visually impaired subscribers with automated ADA compliance suggestions and color contrast adjustments.
- Image Validation. Check for missing alt text and optimize file sizes to ensure your images load quickly and convey meaning effectively.
Pricing Comparison
KingSumo Pricing
- Unlimited giveaways
- Unlimited entrants
- Basic social sharing
- Random winner selection
- KingSumo branding
- Everything in Free, plus:
- Remove KingSumo branding
- Custom branding and logos
- Advanced social media actions
- Email marketing integrations
- One-time payment for life
Email on Acid Pricing
- 1 user seat
- Unlimited email previews
- Campaign Precheck
- Email editor
- Accessibility testing
- Standard support
- Everything in Basics, plus:
- 3 user seats
- Spam testing
- Deliverability insights
- Advanced analytics
- Priority support
Pros & Cons
KingSumo
Pros
- One-time lifetime pricing eliminates monthly subscription costs
- Extremely simple setup process for non-technical users
- Effective viral loop encourages high sharing rates
- Clean and mobile-responsive giveaway landing pages
Cons
- Limited design customization for landing pages
- Free version includes prominent platform branding
- Lacks advanced fraud detection for fake entries
Email on Acid
Pros
- Unlimited testing allows for frequent iterations without extra costs
- Fast rendering speeds for quick campaign turnarounds
- Comprehensive accessibility tools ensure inclusive marketing
- Intuitive interface makes it easy for non-technical users
Cons
- Higher starting price point than some basic competitors
- Spam testing is restricted to higher-tier plans
- Occasional lag when loading a large number of previews