# Spark Mail vs Dev Calc

The clearest difference is rating: Spark Mail at 4.6 against Dev Calc's 2.0. Spark Mail also leads on ads (none vs shown) and update cadence (weekly vs every 2 months). Dev Calc's advantage is iOS requirement (13.0 vs 16.4). On price, review sentiment, in-app purchases and monetization model there is nothing between them.

Both are free to download. Spark Mail sells 13 in-app purchases, starting at $7.99 per month and Dev Calc sells 1 in-app purchase, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

Spark Mail holds the better App Store score, 4.6 against 2.0. That said, the two scores are not equally well evidenced: Spark Mail has 82K ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 61% of Spark Mail's written reviews are positive against 60% of Dev Calc's.

Spark Mail ships an update weekly, Dev Calc every 2 months. The most recent releases landed on September 26, 2026 and June 4, 2026 respectively.

## The numbers

| Metric | Spark Mail | Dev Calc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (82K ratings)](https://appshunter.io/ios/app/spark-mail-ai-email-assistant/id997102246/reviews)** | [2.0 (2 ratings)](https://appshunter.io/ios/app/dev-calc-developer-calculator/id1576503219/reviews) |
| Number of ratings | **82K** | 2 |
| Positive reviews | **61.4% of reviews** | 60.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Weekly** | Every 2 months |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | **#135** | — |
| Size | 382 MB | 51 MB |
| Requires iOS | 16.4 | **13.0** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Readdle Technologies Limited](https://appshunter.io/developer/285035419) | [Toshiya Hondo](https://appshunter.io/developer/1571875732) |

## What reviewers say

### Spark Mail

[App page](https://appshunter.io/ios/app/spark-mail-ai-email-assistant/id997102246)

**Currently charting:** #135 Top Grossing · Productivity (US App Store)

Streamline your email and calendar management with an AI-powered assistant. Organize multiple accounts, declutter your inbox with smart sorting, and use AI to draft replies, summarize threads, and manage your schedule efficiently.

**Highlights:** Unified inbox for multiple email accounts, AI-powered email summarization and drafting, Smart Inbox for prioritizing emails, Calendar management and meeting scheduling, Gatekeeper for sender screening, Team collaboration on emails, Integrations with productivity apps

**Features:** Family Sharing, Apple Wallet, Apple Watch app, Vision Pro support

**In-app purchases (13)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Spark Premium | $7.99 | per month |
| Spark Plus Monthly | $10.00 | per month |
| Spark Premium | $11.99 | per month |
| Spark Pro Monthly | $20.00 | per month |
| Get Spark Premium | $41.99 | per year |
| Spark Premium | $59.99 | per year |
| Get Spark Premium | $59.99 | per year |
| Spark Plus Annual | $99.00 | per year |
| Get Spark Premium | $119.99 | per year |
| Spark Pro Annual | $199.00 | per year |
| Regular Powerbank | $4.99 | one-time |
| Big Powerbank | $9.99 | one-time |
| Huge Powerbank | $19.99 | one-time |

**What reviewers like**

- 🚀 Excellent email management features
- 👍 Clean and intuitive user interface
- 📂 Effective email organization and categorization
- ⏱️ Efficient workflow with snooze, scheduling, and templates
- 💻 Seamless cross-device experience

**What reviewers complain about**

- 🐛 Occasional sync and stability issues
- 🔒 Concerns over privacy and data usage
- 💰 Aggressive push for paid subscription
- 📥 Unreliable notification delivery
- 🔍 Inconsistent search functionality

**Reported bugs**

- Emails disappearing from the inbox
- Delayed email delivery and sync
- Crashes and freezes when opening the app
- Issues with Exchange calendar and account sync
- Incorrect email grouping and threading

**Requested features**

- Improved spam filtering and email blocking
- Option to disable email threading
- Better calendar integration and management
- Customizable email signatures and layouts
- Expanded third-party app integrations


### Dev Calc

[App page](https://appshunter.io/ios/app/dev-calc-developer-calculator/id1576503219)

This app assists developers and programmers with immediate numeric conversions between binary, octal, decimal, and hexadecimal formats. It also provides tools for generating color codes from RGB, HSL, and HSV values, with a color picker and preset options.

**Highlights:** Numeric conversion (Bin, Oct, Dec, Hex), Signed/Unsigned options, Adjustable bit sizes (8, 16, 32, 64), RGB, HSL, HSV color code generation, Color picker, Preset color options

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads (Monthly) | $1.99 | per month |


## Frequently asked questions

### Is Spark Mail free?

Spark Mail is free to download, with in-app purchases available.

### Is Dev Calc free?

Dev Calc is free to download, with in-app purchases available.

### Which has better reviews, Spark Mail or Dev Calc?

Spark Mail is rated higher. Spark Mail averages 4.6 out of 5 from 82K ratings, while Dev Calc averages 2.0 from 2 ratings.

### Do Spark Mail or Dev Calc have ads?

Dev Calc shows ads; Spark Mail does not.

### Which is updated more often, Spark Mail or Dev Calc?

Spark Mail ships an update weekly, and Dev Calc every 2 months. Most recently, Spark Mail was updated on September 26, 2026 and Dev Calc on June 4, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*