> ## Documentation Index > Fetch the complete documentation index at: https://docs.vortexiq.ai/llms.txt > Use this file to discover all available pages before exploring further. # Overall Score: Mobile vs Desktop, Website Performance (PageSpeed + CrUX) > Overall Score: Mobile vs Desktop for Website Performance (PageSpeed + CrUX) stores. Tracked live in Vortex IQ Nerve Centre. How to read it, why it matters,... **Metrics type:** [Supporting Metrics](/nerve-centre/overview#metrics-types-explained) • **Category:** [Website Performance](/nerve-centre/connectors#connectors-by-type) ## At a glance > **Per-template Mobile vs Desktop score comparison**, surfaces the device gap broken out by page type (homepage, PDP, collection, cart, checkout, etc.). Different templates carry different mobile-vs-desktop gap patterns; this card lets the merchant identify which templates need targeted mobile work. **Pairs with [`psi_mobile_vs_desktop_score`](/nerve-centre/kpi-cards/website-performance/mobile-vs-desktop-score)** which gives the site-weighted aggregate; this card decomposes by template. | | | | --------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **What it counts** | Per-template Lighthouse Performance Score for both mobile and desktop profiles, with the gap. Each template represented by its representative URL (e.g. homepage → `/`, PDP → top-traffic product page, collection → top-traffic category). | | **Sample type** | **Lab data** from per-template Lighthouse audits, two runs each (one per device profile). | | **Why per-template matters** | Site-weighted aggregate hides which templates are dragging the average. **A homepage with 22 percent traffic and a 35-point device gap drives more of the aggregate** than 50 tail product pages with a 20-point gap. The per-template view surfaces optimisation priorities. | | **Reading the per-template view** | (1) **Identify worst-gap templates**: typically homepage, collection, top PDPs. (2) **Cross-reference with traffic share**: high-gap × high-traffic = priority focus. (3) **Apply template-level fixes**: image responsive variants on hero templates; widget refactors on collection templates; etc. | | **Currency** | n/a, score values + delta. | | **Time window** | `T/7D` | | **Alert trigger** | `worst-template gap > 40 points`. | | **Sentiment key** | `null` (comparison view). | | **Roles** | owner, marketing, operations | ## Calculation Calculated automatically from your Website Performance (PageSpeed + CrUX) data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading. ## Worked example A UK-based BigCommerce fashion store, per-template comparison Wednesday 15 May 26. | Page template | Mobile score | Desktop score | Gap | Traffic share | Gap × traffic | | ------------------- | -----------: | ------------: | --: | ------------: | ------------: | | Homepage | 42 | 76 | 34 | 22% | **7.5** | | Product detail page | 58 | 82 | 24 | 25% | 6.0 | | Collection page | 48 | 79 | 31 | 28% | **8.7** | | Cart | 62 | 88 | 26 | 8% | 2.1 | | Checkout step 1 | 71 | 92 | 21 | 4% | 0.8 | | Checkout step 2 | 73 | 92 | 19 | 4% | 0.8 | | About / contact | 68 | 90 | 22 | 1% | 0.2 | | Search results | 54 | 80 | 26 | 8% | 2.1 | What the per-template view is telling us: 1. **Collection page has the highest gap × traffic score (8.7).** Despite homepage having the largest gap, collection has higher traffic share, making it the highest-leverage optimisation target. **Fix collection page first**. 2. **The optimisation priority by gap × traffic**: * **Collection page** (8.7): filter widget refactor + responsive images on grid items * **Homepage** (7.5): hero image responsive variants * **PDP** (6.0): hero image responsive variants * **Cart, search results** (2.1 each): low priority * **Checkout, about** (sub-1.0): no work needed 3. **Same fix-pattern across templates** for image-heavy pages: responsive image variants via `srcset`, image format conversion, preload critical images. **One workflow** addresses homepage + PDP + collection-page-grid simultaneously. 4. **Collection page additional work**: filter widget refactor (covered in [`psi_mobile_desktop_inp`](/nerve-centre/kpi-cards/website-performance/responsiveness-mobile-vs-desktop) playbook). The mobile-specific INP issue compounds with the LCP issue on collection. 5. **Realistic post-optimisation forecast** for the worst-3 templates: * Collection: mobile 48 → 70 (gap from 31 → 9) * Homepage: mobile 42 → 65 (gap from 34 → 11) * PDP: mobile 58 → 75 (gap from 24 → 7) * **Site-weighted mobile score**: 51 → 68 6. **Reading the trio with [`psi_mobile_desktop_lcp`](/nerve-centre/kpi-cards/website-performance/load-speed-mobile-vs-desktop), [`psi_mobile_desktop_inp`](/nerve-centre/kpi-cards/website-performance/responsiveness-mobile-vs-desktop), [`psi_mobile_desktop_cls`](/nerve-centre/kpi-cards/website-performance/layout-stability-mobile-vs-desktop)** decomposes which sub-metric drives each template's gap. Collection's gap is INP-dominated; homepage's is LCP-dominated. Different fix focus per template. The diagnostic flow: 1. **Sort templates by gap × traffic.** 2. **Decompose dominant template gaps by sub-metric** using the per-CWV device-gap cards. 3. **Apply template-level fixes**: each template's fix benefits all URLs sharing the template. 4. **Re-audit** to confirm gap reduction. Rapid-response playbook: | Time horizon | Action | | ------------ | --------------------------------------------------- | | First 1 hour | Sort by gap × traffic; identify priority templates. | | First week | Apply highest-leverage template fix. | | Day 28 | Field metrics reflect changes. | ## Sibling cards merchants should reference together | Card | Why merchants reach for it | | ---------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------- | | [`psi_mobile_vs_desktop_score`](/nerve-centre/kpi-cards/website-performance/mobile-vs-desktop-score) | Site-weighted aggregate; this card decomposes by template. | | [`psi_mobile_desktop_lcp`](/nerve-centre/kpi-cards/website-performance/load-speed-mobile-vs-desktop) | LCP gap; cross-reference for sub-metric driver. | | [`psi_mobile_desktop_inp`](/nerve-centre/kpi-cards/website-performance/responsiveness-mobile-vs-desktop) | INP gap. | | [`psi_mobile_desktop_cls`](/nerve-centre/kpi-cards/website-performance/layout-stability-mobile-vs-desktop) | CLS gap. | | [`psi_score_by_template`](/nerve-centre/kpi-cards/website-performance/score-by-template) | Score per template (mobile-only). | | [`psi_lcp_by_template`](/nerve-centre/kpi-cards/website-performance/lcp-by-template) | Per-template LCP. | | [`psi_image_optimisation`](/nerve-centre/kpi-cards/website-performance/image-optimisation) | Common template-level fix. | ## Reconciling against the vendor's own dashboard **Where to look:** * **PageSpeed Insights**, paste each template's representative URL; toggle Mobile/Desktop tabs. * **Lighthouse CI**, runs per-URL audits in build pipeline. **Why the Vortex IQ per-template comparison may differ from manual PSI checks:** | Reason | Direction | What to do | | ---------------------------------------------------------------------------------------------------------------------------- | ---------------- | ---------------------- | | **Template-representative URL choice.** Vortex IQ uses configured representative URLs; manual checks may use different URLs. | Variable | Confirm same URL used. | | **Run-to-run variance.** Each device profile fluctuates ±10-20%. | Either direction | Use 7-day rolling. | **Cross-connector reconciliation:** primarily internal (with the per-CWV device-gap cards and per-URL ranking cards). **Quick rule for support tickets:** the gap × traffic ranking is the actionable view. Don't optimise the template with the largest gap if its traffic share is small; optimise the template with the largest gap × traffic product. ## Known limitations / merchant FAQs **Should I optimise the template with the largest gap or the largest gap × traffic?** Largest gap × traffic. The product determines commercial impact: a 35-point gap on a low-traffic page affects fewer users than a 24-point gap on a high-traffic page. **Why does collection page have a larger gap than homepage?** Filter widget JS. Collection pages run mobile-specific filter logic that desktop doesn't trigger (desktop usually has always-visible filter sidebar). The mobile-only widget compounds the structural CPU gap. **Will fixing one template improve other templates?** Some patterns transfer. Image optimisation in the homepage hero often re-uses the same image-CDN config that benefits PDP and collection images. Filter widget refactor benefits all collection pages simultaneously. **Template fixes have multiplier effects.** **Can Vortex IQ tell me which sub-metric drives each template's gap?** Yes; cross-reference with [`psi_mobile_desktop_lcp`](/nerve-centre/kpi-cards/website-performance/load-speed-mobile-vs-desktop), [`psi_mobile_desktop_inp`](/nerve-centre/kpi-cards/website-performance/responsiveness-mobile-vs-desktop), [`psi_mobile_desktop_cls`](/nerve-centre/kpi-cards/website-performance/layout-stability-mobile-vs-desktop). Each surfaces the per-template breakdown for its sub-metric. *** ### Tracked live in Vortex IQ Nerve Centre *Overall Score: Mobile vs Desktop* is one of hundreds of KPI pulses Vortex IQ tracks across Website Performance (PageSpeed + CrUX) and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English. 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