**Background:** Diabetes mellitus affects approximately 463 million people globally, a number projected to reach 700 million by 2045. In Poland, 2.9 million adults and 22,000 children and adolescents were registered as having diabetes in 2018. The rapid development of diabetes pharmacotherapy has increased life expectancy but also created challenges for healthcare professionals in providing adequate diabetes and nutrition education. Telemedicine and mHealth (mobile wireless technologies for public health) have emerged as potential solutions, accelerated by the COVID-19 pandemic which demonstrated their safety and effectiveness. This narrative review aims to present current knowledge about mobile applications and websites related to diabetes, particularly those focused on nutritional behaviors, and to evaluate selected Polish-language apps for their functionality and potential utility in diabetes management.
**Methods:** The article comprises two parts. The first part reviews published literature on mHealth applications in diabetes care, focusing on evidence-based medicine. The second part involves the authors downloading and evaluating nutritional mobile applications recommended by the Department of Children's Diabetology of the Medical University of Silesia in Katowice. Apps were selected based on four criteria: available in Polish language, designed for nutrient intake control, including special functions for people with diabetes, and available for free. The authors assessed each app for functionality, ease of use, product database, and possible use in diabetes management. Six applications were evaluated: FatSecret, MyFitnessPal, Fitatu, VitaScale, Kalkulator Medtronic, and Kalkulator WBT. Additionally, the paid app 3MC Kalkulator Wymienników was described separately.
**Key Results:** The review of literature indicates that over 90% of respondents in Poland use mobile phones, with 91.2% having internet access on mobile devices. Of approximately 325,000 mobile health applications available, 30% are physical activity monitors and 7.4% are nutritional applications. According to the Research 2 Guidance report, the diabetes treatment sector is identified as having the greatest mHealth potential in the next 5 years, ahead of obesity, depression, hypertension, and coronary heart disease. Multiple studies confirm that mobile app interventions are associated with significant reductions in body weight and waist circumference in type 2 diabetes patients, with greater improvement among obese patients using apps combined with other behavioral components. Nine randomized controlled trials showed that smartphone nutrition apps led patients to choose higher quality, lower calorie, low-fat foods and engage in more intense physical activity, resulting in significantly greater weight loss compared to non-users. However, evidence for type 1 diabetes remains limited to single observational and case-control studies. A Greek randomized controlled trial with 80 participants using the Euglyca© app found statistically significant lower HbA1c values at all 3-month time points over one year, along with a positive correlation between Diabetes Treatment Satisfaction Questionnaire scores and normoglycemia rates. A Swiss study using the Webdia© app showed a 0.33% reduction in HbA1c over three months without increasing hypoglycemia prevalence, particularly in patients with baseline HbA1c above 8.0%. The GoCarb application, which analyzes meals via voice description, demonstrated accuracy up to 10g of carbohydrates in 96% of analyzed products compared to professional dietitian calculations. Despite the proliferation of apps, the Australian MILES-2 cross-sectional survey found that only 24% of adults with type 1 diabetes and 8% with type 2 diabetes use apps for self-management. Among 1,682 participants in Kebede's study, more than half of type 1 and two-thirds of type 2 diabetes patients used mHealth apps, with self-monitoring of glycemia being the most popular function and food diaries the second most common. Notably, only 14 apps in the App Store and Google Play in 2016 had FDA approval or CE marking, and a systematic review found only 7.1% of 794 analyzed apps on the Spanish market were based on scientific evidence. Among 370 self-administered glycemic management apps analyzed, only 10% trained users in glycemic management and approximately one-third had goals and reminders for regular blood glucose and HbA1c measurement. The evaluation of six selected Polish-language apps revealed that FatSecret, MyFitnessPal, Fitatu, and VitaScale all include food diaries and calorie/nutrient calculators, while Kalkulator Medtronic and Kalkulator WBT lack food diaries. Only Fitatu and VitaScale include exchanger calculators, and only VitaScale includes a bolus calculator. Google Play ratings ranged from 4.4/5 (MyFitnessPal) to 4.8/5 (VitaScale), and Apple Store ratings from 4.6/5 (Fitatu) to 5/5 (Kalkulator WBT). MyFitnessPal was rated as difficult to use, while FatSecret, Fitatu, VitaScale, and Kalkulator WBT were rated as very simple.
**Clinical Implications:** The authors conclude that dietary mobile applications and websites represent an effective way to prevent diabetes progression and improve quality of life. Nutrition calculators in apps allow for faster and more accurate calculation of nutritional values compared to traditional methods like printed tables. However, a significant number of patients decline to use these solutions due to insufficient personalization options. The authors recommend that additional diabetes-specific features such as exchanger calculators, glycemic index, and glycemic load information could encourage wider adoption. They emphasize that healthcare professionals should maintain up-to-date knowledge of available and suitable applications to guide patients effectively. The authors also caution that many apps lack clinical trials and may not align with current clinical guidelines, advising patients to verify apps before installing and choose those recommended by scientific societies. The review is limited by its narrative design and the small, non-systematic sample of apps evaluated.