Comparison

CTC vs STI Tx Guide

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

CTC

This medical reference app provides quick access to standardized adverse event criteria and grading scales for oncology research. It allows for efficient logging, tracking, and reporting of patient events, including performance scores and custom entries. Data is kept strictly on-device for privacy and compliance.

Highlights
  • CTCAE v4 and v5 reference
  • Performance score integration (Karnofsky, ECOG, Lansky)
  • Advanced adverse event logger
  • Custom event creation
  • CSV data import/export
  • On-device data storage
Read full description

CTC-AE is a reference and educational tool for clinical researchers, oncologists, and healthcare professionals working with adverse event terminology and oncology performance status scales. The app provides fast, offline access to publicly available standards: • NCI Common Terminology Criteria for Adverse Events (CTC-AE v4.03 and v5.0) • ECOG Performance Status • Karnofsky Performance Status • Lansky Performance Status (pediatric) You can also keep personal reference notes about trials and patients, stored privately in your own iCloud account and synced across your Apple devices. Export your data as CSV at any time. KEY FEATURES • Complete CTC-AE v4.03 and v5.0 terminology with grades and definitions • Color-coded severity grades for quick visual reference • Multi-column layout optimized for iPad • Performance status scales (ECOG, Karnofsky, Lansky) • Personal trial and patient reference notes, stored privately in your own iCloud account and synced across iPhone, iPad, and Mac • CSV export • Optional Face ID / Touch ID protection • Optional name scrambling for on-screen privacy PRIVACY Your reference notes live in your private iCloud container. Arpacore B.V. has no access to this data, and no information is shared with any third party. INTENDED USE CTC-AE is intended for educational and reference purposes only. It is not a medical device. It is not intended to diagnose, prevent, monitor, predict, prognose, or treat any disease, injury, or disability, and does not provide medical advice. All clinical decisions remain the sole responsibility of qualified healthcare professionals. The CTC-AE terminology is published by the U.S. National Cancer Institute and is reproduced here for reference. This app is not affiliated with, endorsed by, or sponsored by the NCI or NIH. CTC-AE is also available natively on Mac, with full sync between your devices.

About

STI Tx Guide

Provides healthcare professionals with up-to-date, evidence-based recommendations for the prevention, diagnosis, and treatment of sexually transmitted infections. Features include clinical care guidance, sexual history resources, and patient materials for effective patient management.

Highlights
  • STI prevention recommendations
  • Diagnosis guidance
  • Treatment protocols
  • Clinical care assistance
  • Sexual history resources
  • Patient management tools
Features
Read full description

The new app offers quick and easy access to streamlined STI prevention, diagnosis, and treatment recommendations. The user-friendly interface includes more clinical care guidance, sexual history resources, patient materials, and other features to assist with patient management. The STI Treatment (Tx) Guidelines mobile app serves as a quick reference guide for doctors and related parties on the identification of and treatment for sexually transmitted diseases (STDs). The full STI Treatment Guidelines (cdc.gov) can be accessed at https://www.cdc.gov/std/treatment-guidelines/default.htm. The guidelines provide current evidence-based prevention, diagnostic and treatment recommendations that replace the 2015 guidance. The recommendations are intended to be a source for clinical guidance. Healthcare providers should always assess patients based on their clinical circumstances and local burden. DISCLAIMER THE MATERIALS EMBODIED IN THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC) OR THE UNITED STATES (U.S.) GOVERNMENT BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, LOSS OF PROFIT, LOSE OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF THIRD PARTIES, WHETHER OR NOT CDC OR THE U.S. GOVERNMENT HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.

Screenshots

CTC4 screens
STI Tx Guide4 screens

Verdict

The call

The clearest difference is price: STI Tx Guide at Free against CTC's $3.99. STI Tx Guide also leads on in-app purchases (none vs 1) and iOS requirement (15.0 vs 17.6). CTC's advantage is review sentiment (56% vs 36%). On update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

STI Tx Guide is free to download; CTC costs $3.99 up front. CTC sells 1 one-off in-app purchase. STI Tx Guide asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on September 13, 2026 and August 28, 2026 respectively.

Scorecard5 real differences · 5 level
CTC versus STI Tx Guide: the parameters behind the verdict, then further details
ParameterCTCSTI Tx Guide
Price$3.99Free — better
Rating—3.5 (36 ratings) — better
Positive reviews55.6% of reviews — better35.7% of reviews
Number of ratings—36 — better
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationPaidFree — better
DevicesiPhone, iPad, Mac — betteriPhone, iPod
Requires iOS17.615.0 — better
Further details — not scored
Size2 MB36 MB
Age rating17+12+
DeveloperArpacore B.V.Centers For Disease Control and Prevention

Customer experience

CTC

Written reviews9 reviews
Positive55.6%
Neutral33.3%
Negative11.1%

STI Tx Guide

All ratings36 ratings
Positive63.9%
Neutral2.8%
Negative33.3%
Written reviews14 reviews
Positive35.7%
Neutral7.1%
Negative57.1%

In-app purchases

1 purchases

CTC

One-time1
  • Adverse Event Logger$3.99
None

STI Tx Guide

No in-app purchases

Questions

Is CTC free?
CTC costs $3.99, and also offers in-app purchases.
Is STI Tx Guide free?
STI Tx Guide is free to download, with no in-app purchases.
Do CTC or STI Tx Guide have ads?
Neither CTC nor STI Tx Guide shows ads.
Which is updated more often, CTC or STI Tx Guide?
CTC ships an update every 2 months, and STI Tx Guide every 2 months. Most recently, CTC was updated on September 13, 2026 and STI Tx Guide on August 28, 2026.

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